In VS 2012, my application works correctly when in I build with .net 3.5 client profile. It's a simple standalone app that's reads data from from 2 text files and then outputs some text files. Debug and and release exe's execute as standalone with .net 3.5. But with when I build with .net 4.0 client profile only the debug exe reads the input files, not the release exe. It works in the IDE. Any insight would be appreciated.