Unable to copy file "obj\x86\Debug\*.exe" to "bin\Debug\*.exe". The process cannot access the file 'bin\Debug\*.exe' because it is being used by another process.

To release the file go to the Task Manager and see if the Exe is running in the process Tab. Kill the process and Build the project it should work.

But before that make sure why the Exe was still running in the process even after the application is termninated. It might be due to some malperformance of garbage collection