Compiler Warning (level 4) CS1610
Unable to delete temporary file 'file' used for default Win32 resource -- resource
When using the /win32res compiler option and when your %TEMP% directory does not have DELETE permission, this warning indicates that the compiler could not delete a temporary file that it created.
Make sure that you have read/write/delete permissions for the %TEMP% directory.
If necessary, you can manually delete these files and there will be no harm to C# or any of your programs.