Visual Studio locks output file on build

Question

I have a simple WinForms solution in VS 2010. Whenever I build it, output file (bin\\debug\\app.exe) ends up locked, and subsequent builds fail with a message like \"

Answer 1

I ran into the same thing developing xamarin apps in VS2017.

It happened to be Windows Defender locking the exe/dll with devenv.exe.

You can go to Win Defender and add

devenv.exe
msbuild.exe

to the process exclusion list.