error MSB4126: The specified solution configuration "Release|" is invalid.

Hi
New to Unity.
Things were going OK but now suddenly my game project won't build any more, no idea why.
I keep getting the error below. No idea where to look for a solution or how to fix this.
Are these random failures common in Unity?

Thanks

BuildFailedException: Failed to build Visual Studio project using arguments 'C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Current\Bin\MSBuild.exe "C:\Users\mike\Pumpkinhead\build\2DFromScratch.sln" /nologo /maxcpucount /p:Configuration=Release /platform= /p:SolutionDir="C:\\Users\\mike\\Pumpkinhead\\build\\" /t:Build /clp:Verbosity=minimal'.
Output:C:\Users\mike\Pumpkinhead\build\2DFromScratch.sln.metaproj : error MSB4126: The specified solution configuration "Release|" is invalid. Please specify a valid solution configuration using the Configuration and Platform properties (e.g. MSBuild.exe Solution.sln /p:Configuration=Debug /platform="Any CPU") or leave those properties blank to use the default solution configuration.

 

The build config seems to be named „Release|“ which indicates so,ething is off.
Try deleting .csproj and .sln files and restart VS.

 

I`m dealing with the same task. I had similar error but output log was complete. Try to add the platform parameter.

/platform=x64