Hey @Red7Projects and welcome!
If you don't want to edit the MonoGame.Content.Builder.targets file, you could also do this in your .csproj file:
This removes the /quite argument so that when compiling your project again, you will get additional information in your output window.
Do that and post the output log in this thread so we could take a look what went wrong.
You could also try to double click the mgcb file and compile it manually. Maybe the pipeline tool will show you the error directly.