diff --git a/src/Containers/Microsoft.NET.Build.Containers/KnownStrings.cs b/src/Containers/Microsoft.NET.Build.Containers/KnownStrings.cs
index 492027a1f41d..371edab873a6 100644
--- a/src/Containers/Microsoft.NET.Build.Containers/KnownStrings.cs
+++ b/src/Containers/Microsoft.NET.Build.Containers/KnownStrings.cs
@@ -49,8 +49,14 @@ public static class Items
 
     public static class ErrorCodes
     {
+        // current version doesn't support containerization
         public static readonly string CONTAINER002 = nameof(CONTAINER002);
+        // containerimagename rename
         public static readonly string CONTAINER003 = nameof(CONTAINER003);
+        // generic http error
+        public static readonly string CONTAINER004 = nameof(CONTAINER004);
+        // don't use the containers package
+        public static readonly string CONTAINER005 = nameof(CONTAINER005);
         public static readonly string CONTAINER1011 = nameof(CONTAINER1011);
         public static readonly string CONTAINER1012 = nameof(CONTAINER1012);
         public static readonly string CONTAINER1013 = nameof(CONTAINER1013);
diff --git a/src/Containers/packaging/build/Microsoft.NET.Build.Containers.targets b/src/Containers/packaging/build/Microsoft.NET.Build.Containers.targets
index 9f4796558438..11589947cc51 100644
--- a/src/Containers/packaging/build/Microsoft.NET.Build.Containers.targets
+++ b/src/Containers/packaging/build/Microsoft.NET.Build.Containers.targets
@@ -221,6 +221,7 @@
           ($(_SdkCanPublishWorker) and $(_IsWorkerProject)) or
           ($(_SdkCanPublishConsole) and '$(EnableSdkContainerSupport)' == 'true')
         )"
+      Code="CONTAINER005"
       Text="The $(_ContainersPackageIdentity) NuGet package is explicitly referenced but the current SDK can natively publish the project as a container. Consider removing the package reference to $(_ContainersPackageIdentity) because it is no longer needed." />
 
     <PropertyGroup>