ASPNETCOMPILER : error ASPRUNTIME: Could not find a part of the path 'C:\app\%ProgramFiles(x86)%\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn\csc.exe'

[mrmonday]

Using the following:

WebApplication1.zip

Expand-Archive .\WebApplication1.zip -DestinationPath .
cd .\WebApplication1\
docker build --no-cache .

Gives:

Sending build context to Docker daemon  25.09kB
Step 1/4 : FROM mcr.microsoft.com/dotnet/framework/sdk:4.8-windowsservercore-ltsc2019 AS build
 ---> c4fa4ec9c73e
Step 2/4 : WORKDIR /app
 ---> Running in 5d2edf2f54fe
Removing intermediate container 5d2edf2f54fe
 ---> 694583181127
Step 3/4 : COPY . .
 ---> 201713b7dc71
Step 4/4 : RUN $toolsDirectory = \"${Env:ProgramFiles(x86)}\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.8 Tools\"; msbuild.exe /property:AspnetMergePath=\"$toolsDirectory\" /restore /property:DeployOnBuild=true /property:PublishProfile=FolderProfile WebApplication1.csproj
 ---> Running in 20fef5f0b677
Microsoft (R) Build Engine version 16.1.76+g14b0a930a7 for .NET Framework
Copyright (C) Microsoft Corporation. All rights reserved.

Build started 7/18/2019 1:15:01 PM.
Project "C:\app\WebApplication1.csproj" on node 1 (Restore target(s)).
Restore:
  Restoring packages for C:\app\WebApplication1.csproj...
    GET https://api.nuget.org/v3-flatcontainer/microsoft.codedom.providers.dotnetcompilerplatform/index.json
    OK https://api.nuget.org/v3-flatcontainer/microsoft.codedom.providers.dotnetcompilerplatform/index.json 395ms
    GET https://api.nuget.org/v3-flatcontainer/microsoft.codedom.providers.dotnetcompilerplatform/2.0.1/microsoft.codedom.providers.dotnetcompilerplatform.2.0.1.nupkg
    OK https://api.nuget.org/v3-flatcontainer/microsoft.codedom.providers.dotnetcompilerplatform/2.0.1/microsoft.codedom.providers.dotnetcompilerplatform.2.0.1.nupkg 19ms
  Installing Microsoft.CodeDom.Providers.DotNetCompilerPlatform 2.0.1.
  Committing restore...
  Generating MSBuild file C:\app\obj\WebApplication1.csproj.nuget.g.props.
  Generating MSBuild file C:\app\obj\WebApplication1.csproj.nuget.g.targets.
  Writing assets file to disk. Path: C:\app\obj\project.assets.json
  Restore completed in 6.66 sec for C:\app\WebApplication1.csproj.

  NuGet Config files used:
      C:\Users\ContainerAdministrator\AppData\Roaming\NuGet\NuGet.Config

  Feeds used:
      https://api.nuget.org/v3/index.json

  Installed:
      1 package(s) to C:\app\WebApplication1.csproj
Done Building Project "C:\app\WebApplication1.csproj" (Restore target(s)).
Project "C:\app\WebApplication1.csproj" on node 1 (default targets).
PrepareForBuild:
  Creating directory "bin\".
  Creating directory "obj\Debug\".
CoreCompile:
  C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn\csc.exe /noconfig /nowarn:1701,1702 /nostdlib+ /errorreport:prompt /warn:4 /define:DEBUG;TRACE /highentropyva+ /reference:C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\lib\net45\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\Microsoft.CSharp.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\mscorlib.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.ComponentModel.DataAnnotations.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Configuration.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Core.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Data.DataSetExtensions.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Data.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Drawing.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.EnterpriseServices.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.ApplicationServices.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.DynamicData.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.Entity.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.Extensions.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Web.Services.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Xml.dll" /reference:"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Xml.Linq.dll" /debug- /debug:full /optimize- /out:obj\Debug\WebApplication1.dll /subsystemversion:6.00 /target:library /utf8output Properties\AssemblyInfo.cs WebForm1.aspx.cs WebForm1.aspx.designer.cs "C:\Users\ContainerAdministrator\AppData\Local\Temp\.NETFramework,Version=v4.8.AssemblyAttributes.cs"
  Using shared compilation with compiler from directory: C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn
_CopyFilesMarkedCopyLocal:
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\lib\net45\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll" to "C:\app\bin\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll".
  Creating "C:\app\obj\Debug\WebApplication1.csproj.CopyComplete" because "AlwaysCreate" was specified.
_CopyAppConfigFile:
  Copying file from "C:\app\Web.config" to "C:\app\bin\WebApplication1.dll.config".
CopyFilesToOutputDirectory:
  Copying file from "C:\app\obj\Debug\WebApplication1.dll" to "C:\app\bin\WebApplication1.dll".
  WebApplication1 -> C:\app\bin\WebApplication1.dll
  Copying file from "C:\app\obj\Debug\WebApplication1.pdb" to "C:\app\bin\WebApplication1.pdb".
CopyRoslynCompilerFilesToOutputDirectory:
  Creating directory "C:\app\bin\roslyn".
  Creating directory "C:\app\bin\roslyn".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csc.exe.config" to "C:\app\bin\roslyn\csc.exe.config".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csc.exe" to "C:\app\bin\roslyn\csc.exe".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csi.exe" to "C:\app\bin\roslyn\csi.exe".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csi.exe.config" to "C:\app\bin\roslyn\csi.exe.config".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.Build.Tasks.CodeAnalysis.dll" to "C:\app\bin\roslyn\Microsoft.Build.Tasks.CodeAnalysis.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CodeAnalysis.CSharp.dll" to "C:\app\bin\roslyn\Microsoft.CodeAnalysis.CSharp.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csi.rsp" to "C:\app\bin\roslyn\csi.rsp".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CodeAnalysis.CSharp.Scripting.dll" to "C:\app\bin\roslyn\Microsoft.CodeAnalysis.CSharp.Scripting.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CodeAnalysis.dll" to "C:\app\bin\roslyn\Microsoft.CodeAnalysis.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CodeAnalysis.VisualBasic.dll" to "C:\app\bin\roslyn\Microsoft.CodeAnalysis.VisualBasic.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CSharp.Core.targets" to "C:\app\bin\roslyn\Microsoft.CSharp.Core.targets".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.DiaSymReader.Native.amd64.dll" to "C:\app\bin\roslyn\Microsoft.DiaSymReader.Native.amd64.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.DiaSymReader.Native.x86.dll" to "C:\app\bin\roslyn\Microsoft.DiaSymReader.Native.x86.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.Managed.Core.targets" to "C:\app\bin\roslyn\Microsoft.Managed.Core.targets".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.VisualBasic.Core.targets" to "C:\app\bin\roslyn\Microsoft.VisualBasic.Core.targets".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.Win32.Primitives.dll" to "C:\app\bin\roslyn\Microsoft.Win32.Primitives.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.AppContext.dll" to "C:\app\bin\roslyn\System.AppContext.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Collections.Immutable.dll" to "C:\app\bin\roslyn\System.Collections.Immutable.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Console.dll" to "C:\app\bin\roslyn\System.Console.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Diagnostics.DiagnosticSource.dll" to "C:\app\bin\roslyn\System.Diagnostics.DiagnosticSource.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Diagnostics.FileVersionInfo.dll" to "C:\app\bin\roslyn\System.Diagnostics.FileVersionInfo.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Diagnostics.StackTrace.dll" to "C:\app\bin\roslyn\System.Diagnostics.StackTrace.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Globalization.Calendars.dll" to "C:\app\bin\roslyn\System.Globalization.Calendars.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.IO.Compression.dll" to "C:\app\bin\roslyn\System.IO.Compression.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\csc.rsp" to "C:\app\bin\roslyn\csc.rsp".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.IO.Compression.ZipFile.dll" to "C:\app\bin\roslyn\System.IO.Compression.ZipFile.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.IO.FileSystem.dll" to "C:\app\bin\roslyn\System.IO.FileSystem.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.IO.FileSystem.Primitives.dll" to "C:\app\bin\roslyn\System.IO.FileSystem.Primitives.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Net.Http.dll" to "C:\app\bin\roslyn\System.Net.Http.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Net.Sockets.dll" to "C:\app\bin\roslyn\System.Net.Sockets.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\Microsoft.CodeAnalysis.Scripting.dll" to "C:\app\bin\roslyn\Microsoft.CodeAnalysis.Scripting.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Reflection.Metadata.dll" to "C:\app\bin\roslyn\System.Reflection.Metadata.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Security.Cryptography.Encoding.dll" to "C:\app\bin\roslyn\System.Security.Cryptography.Encoding.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Security.Cryptography.Primitives.dll" to "C:\app\bin\roslyn\System.Security.Cryptography.Primitives.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Text.Encoding.CodePages.dll" to "C:\app\bin\roslyn\System.Text.Encoding.CodePages.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Security.Cryptography.X509Certificates.dll" to "C:\app\bin\roslyn\System.Security.Cryptography.X509Certificates.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Threading.Tasks.Extensions.dll" to "C:\app\bin\roslyn\System.Threading.Tasks.Extensions.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.ValueTuple.dll" to "C:\app\bin\roslyn\System.ValueTuple.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Xml.ReaderWriter.dll" to "C:\app\bin\roslyn\System.Xml.ReaderWriter.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Runtime.InteropServices.RuntimeInformation.dll" to "C:\app\bin\roslyn\System.Runtime.InteropServices.RuntimeInformation.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Xml.XmlDocument.dll" to "C:\app\bin\roslyn\System.Xml.XmlDocument.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Xml.XPath.dll" to "C:\app\bin\roslyn\System.Xml.XPath.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Security.Cryptography.Algorithms.dll" to "C:\app\bin\roslyn\System.Security.Cryptography.Algorithms.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\System.Xml.XPath.XDocument.dll" to "C:\app\bin\roslyn\System.Xml.XPath.XDocument.dll".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\vbc.exe" to "C:\app\bin\roslyn\vbc.exe".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\vbc.exe.config" to "C:\app\bin\roslyn\vbc.exe.config".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\vbc.rsp" to "C:\app\bin\roslyn\vbc.rsp".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\VBCSCompiler.exe" to "C:\app\bin\roslyn\VBCSCompiler.exe".
  Copying file from "C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\tools\roslynlatest\VBCSCompiler.exe.config" to "C:\app\bin\roslyn\VBCSCompiler.exe.config".
ValidatePublishProfileSettings:
  Validating PublishProfile(FolderProfile) settings.
ValidateGlobalPackageSetting:
  $(PackageAsSingleFile) is True
  $(PackageFileName) is obj\Debug\Package\WebApplication1.zip. Validating...
CollectFilesFromIntermediateAssembly:
  Gather all files from Project items @(IntermediateAssembly). Adding:
  bin\WebApplication1.dll to bin\WebApplication1.dll
  bin\WebApplication1.pdb to bin\WebApplication1.pdb
CollectFilesFromContent:
  Gather all files from Project items @(Content). Adding:
  WebForm1.aspx;Web.config
CollectFilesFromIntermediateSatelliteAssembliesWithTargetPath:
  Gather all files from Project output (IntermediateSatelliteAssembliesWithTargetPath). Adding:
CollectFilesFromReference:
  Gather all files from Project items @(ReferenceCopyLocalPaths,ReferenceComWrappersToCopyLocal,ResolvedIsolatedComModules,_DeploymentLooseManifestFile,NativeReferenceFile).
CollectFilesFromAllExtraReferenceFiles:
  Gather all files from Project items @(AllExtraReferenceFiles). Adding:
CollectFilesFrom_binDeployableAssemblies:
  Gather all files from Project items @(_binDeployableAssemblies). Adding:
PipelineCollectFilesPhase:
  Publish Pipeline Collect Files Phase
PreTransformWebConfig:
  Found The following for Config tranformation:
  Web.config
  Creating directory "C:\app\obj\Debug\TransformWebConfig\transformed\".
  Copying Web.config to obj\Debug\TransformWebConfig\original\Web.config.
  Copying C:\app\Web.Debug.config to obj\Debug\TransformWebConfig\assist\Web.config.
TransformWebConfigCore:
  Transforming Source File: C:\app\Web.config
    Applying Transform File: C:\app\Web.Debug.config
    Output File: obj\Debug\TransformWebConfig\transformed\Web.config
  Transformation succeeded
PostTransformWebConfig:
  Transformed Web.config using C:\app\Web.Debug.config into obj\Debug\TransformWebConfig\transformed\Web.config.
PreProfileTransformWebConfig:
  Creating directory "C:\app\obj\Debug\ProfileTransformWebConfig\transformed\".
PipelineTransformPhase:
  Publish Pipeline Transform Phase
CopyAllFilesToSingleFolderForAspNetCompileMerge:
  Creating directory "obj\Debug\AspnetCompileMerge\Source".
  Copying all files to temporary location below for package/publish:
  obj\Debug\AspnetCompileMerge\Source.
  Copying bin\WebApplication1.dll to obj\Debug\AspnetCompileMerge\Source\bin\WebApplication1.dll.
  Copying bin\WebApplication1.pdb to obj\Debug\AspnetCompileMerge\Source\bin\WebApplication1.pdb.
  Copying WebForm1.aspx to obj\Debug\AspnetCompileMerge\Source\WebForm1.aspx.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\lib\net45\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll to obj\Debug\AspnetCompileMerge\Source\bin\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csc.exe to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csc.exe.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csc.exe.config to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csc.exe.config.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csc.rsp to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csc.rsp.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csi.exe to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csi.exe.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csi.exe.config to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csi.exe.config.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\csi.rsp to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\csi.rsp.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.Build.Tasks.CodeAnalysis.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.Build.Tasks.CodeAnalysis.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CodeAnalysis.CSharp.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CodeAnalysis.CSharp.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CodeAnalysis.CSharp.Scripting.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CodeAnalysis.CSharp.Scripting.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CodeAnalysis.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CodeAnalysis.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CodeAnalysis.Scripting.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CodeAnalysis.Scripting.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CodeAnalysis.VisualBasic.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CodeAnalysis.VisualBasic.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.CSharp.Core.targets to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.CSharp.Core.targets.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.DiaSymReader.Native.amd64.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.DiaSymReader.Native.amd64.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.DiaSymReader.Native.x86.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.DiaSymReader.Native.x86.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.Managed.Core.targets to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.Managed.Core.targets.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.VisualBasic.Core.targets to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.VisualBasic.Core.targets.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\Microsoft.Win32.Primitives.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\Microsoft.Win32.Primitives.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.AppContext.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.AppContext.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Collections.Immutable.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Collections.Immutable.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Console.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Console.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Diagnostics.DiagnosticSource.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Diagnostics.DiagnosticSource.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Diagnostics.FileVersionInfo.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Diagnostics.FileVersionInfo.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Diagnostics.StackTrace.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Diagnostics.StackTrace.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Globalization.Calendars.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Globalization.Calendars.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.IO.Compression.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.IO.Compression.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.IO.Compression.ZipFile.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.IO.Compression.ZipFile.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.IO.FileSystem.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.IO.FileSystem.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.IO.FileSystem.Primitives.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.IO.FileSystem.Primitives.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Net.Http.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Net.Http.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Net.Sockets.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Net.Sockets.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Reflection.Metadata.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Reflection.Metadata.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Runtime.InteropServices.RuntimeInformation.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Runtime.InteropServices.RuntimeInformation.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Security.Cryptography.Algorithms.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Security.Cryptography.Algorithms.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Security.Cryptography.Encoding.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Security.Cryptography.Encoding.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Security.Cryptography.Primitives.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Security.Cryptography.Primitives.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Security.Cryptography.X509Certificates.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Security.Cryptography.X509Certificates.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Text.Encoding.CodePages.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Text.Encoding.CodePages.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Threading.Tasks.Extensions.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Threading.Tasks.Extensions.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.ValueTuple.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.ValueTuple.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Xml.ReaderWriter.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Xml.ReaderWriter.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Xml.XmlDocument.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Xml.XmlDocument.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Xml.XPath.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Xml.XPath.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\System.Xml.XPath.XDocument.dll to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\System.Xml.XPath.XDocument.dll.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\vbc.exe to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\vbc.exe.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\vbc.exe.config to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\vbc.exe.config.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\vbc.rsp to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\vbc.rsp.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\VBCSCompiler.exe to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\VBCSCompiler.exe.
  Copying C:\Users\ContainerAdministrator\.nuget\packages\microsoft.codedom.providers.dotnetcompilerplatform\2.0.1\build\net46\..\..\tools\roslynlatest\VBCSCompiler.exe.config to obj\Debug\AspnetCompileMerge\Source\bin\roslyn\VBCSCompiler.exe.config.
  Copying obj\Debug\TransformWebConfig\transformed\Web.config to obj\Debug\AspnetCompileMerge\Source\Web.config.
AspNetPreCompile:
  C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_compiler.exe -v / -p C:\app\obj\Debug\AspnetCompileMerge\Source -c C:\app\obj\Debug\AspnetCompileMerge\TempBuildDir
ASPNETCOMPILER : error ASPRUNTIME: Could not find a part of the path 'C:\app\%ProgramFiles(x86)%\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn\csc.exe'. [C:\app\WebApplication1.csproj]
Done Building Project "C:\app\WebApplication1.csproj" (default targets) -- FAILED.

Build FAILED.

"C:\app\WebApplication1.csproj" (default target) (1:7) ->
(AspNetPreCompile target) ->
  ASPNETCOMPILER : error ASPRUNTIME: Could not find a part of the path 'C:\app\%ProgramFiles(x86)%\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn\csc.exe'. [C:\app\WebApplication1.csproj]

    0 Warning(s)
    1 Error(s)

Time Elapsed 00:00:11.62
The command 'powershell -Command $ErrorActionPreference = 'Stop'; $ProgressPreference = 'SilentlyContinue'; $toolsDirectory = \"${Env:ProgramFiles(x86)}\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.8 Tools\"; msbuild.exe /property:AspnetMergePath=\"$toolsDirectory\" /restore /property:DeployOnBuild=true /property:PublishProfile=FolderProfile WebApplication1.csproj' returned a non-zero code: 1

If you uncomment the other RUN line in the docker file, the build succeeds.

RUN $toolsDirectory = \"${Env:ProgramFiles(x86)}\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.8 Tools\"; Remove-Item Env:\ROSLYN_COMPILER_LOCATION; msbuild.exe /property:AspnetMergePath=\"$toolsDirectory\" /restore /property:DeployOnBuild=true /property:PublishProfile=FolderProfile WebApplication1.csproj
#RUN $toolsDirectory = \"${Env:ProgramFiles(x86)}\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.8 Tools\"; msbuild.exe /property:AspnetMergePath=\"$toolsDirectory\" /restore /property:DeployOnBuild=true /property:PublishProfile=FolderProfile WebApplication1.csproj

[mthalman]

This is a regression caused by #291

To workaround this, add this line to your Dockerfile prior to calling msbuild:

ENV ROSLYN_COMPILER_LOCATION "C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\Roslyn"

[mthalman]

This has been fixed in the latest images that were published last Wednesday, August 14. See the latest tags on Docker Hub. Be sure to re-pull the image if you're using a shared/floating tag.