diff --git a/CMake/Modules/FindBuildUtils.cmake b/CMake/Modules/FindBuildUtils.cmake
index 5ddfee071f..bc29809ffe 100644
--- a/CMake/Modules/FindBuildUtils.cmake
+++ b/CMake/Modules/FindBuildUtils.cmake
@@ -6,20 +6,23 @@
 function(NF_GENERATE_DFU_PACKAGE FILE1 ADDRESS1 FILE2 ADDRESS2 OUTPUTFILENAME)
 
     add_custom_command(
+            
         TARGET ${NANOCLR_PROJECT_NAME}.elf POST_BUILD
+
         COMMAND ${TOOL_HEX2DFU_PREFIX}/hex2dfu 
-        
+
         -b="${FILE1}" -a="${ADDRESS1}"
         -b="${FILE2}" -a="${ADDRESS2}"
         -o="${OUTPUTFILENAME}"
-        
+
         WORKING_DIRECTORY ${TOOL_HEX2DFU_PREFIX} 
-        
-        DEPENDS ${FILE1} ${FILE2}
 
         COMMENT "exporting bin files to DFU image" 
     )
 
+    # need to add a dependency of NANOCLR to NANOBOOTER because DFU util needs bin outputs of both targets
+    add_dependencies(${NANOCLR_PROJECT_NAME}.elf ${NANOBOOTER_PROJECT_NAME}.elf)
+
 endfunction()
 
 function(NF_GENERATE_BUILD_OUTPUT_FILES TARGET)
diff --git a/targets/CMSIS-OS/ChibiOS/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/CMakeLists.txt
index 1182db95b5..1e56887551 100644
--- a/targets/CMSIS-OS/ChibiOS/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/CMakeLists.txt
@@ -7,19 +7,16 @@ include(STM32_CubePackage)
 
 ########################################################
 # check availability of hex2dfu tool if specified
-# only relevant if this is running on a Windows machine
-if(WIN32)
-    if(NOT "${TOOL_HEX2DFU_PREFIX}" STREQUAL "")
-        if(NOT EXISTS ${TOOL_HEX2DFU_PREFIX}/hex2dfu.exe)
-            message(STATUS "")
-            message(STATUS "Couldn't find the hex2dfu tool at the specified path: ${TOOL_HEX2DFU_PREFIX}/hex2dfu.exe")
-            message(STATUS "Make sure that the CMake option TOOL_HEX2DFU_PREFIX has the correct path.")
-            message(STATUS "If you don't have this tool download it from https://github.com/nanoframework/nf-tools/releases")
-            message(STATUS "")
-            message(FATAL_ERROR "hex2dfu tool not found")
-        else()
-            set(HEX2DFU_TOOL_AVAILABLE TRUE CACHE INTERNAL "hex2dfu tool available")
-        endif()
+if(NOT "${TOOL_HEX2DFU_PREFIX}" STREQUAL "")
+    if(NOT EXISTS ${TOOL_HEX2DFU_PREFIX}/hex2dfu.exe)
+        message(STATUS "")
+        message(STATUS "Couldn't find the hex2dfu tool at the specified path: ${TOOL_HEX2DFU_PREFIX}/hex2dfu.exe")
+        message(STATUS "Make sure that the CMake option TOOL_HEX2DFU_PREFIX has the correct path.")
+        message(STATUS "If you don't have this tool download it from https://github.com/nanoframework/nf-tools/releases")
+        message(STATUS "")
+        message(FATAL_ERROR "hex2dfu tool not found")
+    else()
+        set(HEX2DFU_TOOL_AVAILABLE TRUE CACHE INTERNAL "hex2dfu tool available")
     endif()
 endif()
 
diff --git a/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
index 01d62d2687..904d02695f 100644
--- a/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
@@ -235,7 +235,7 @@ if(HEX2DFU_TOOL_AVAILABLE)
         NF_GENERATE_DFU_PACKAGE(
             ${PROJECT_SOURCE_DIR}/build/${NANOBOOTER_PROJECT_NAME}.bin 08000000 
             ${PROJECT_SOURCE_DIR}/build/${NANOCLR_PROJECT_NAME}.bin 08004000 
-            ${PROJECT_SOURCE_DIR}/build/nanobooter-nanoclr.dfu
+            ${PROJECT_SOURCE_DIR}/build/nanobooter-nanoclr.dfu       
         )
     endif()