Dot net Framework Conflict?

Question

I have done a Windows App using Dot net framework 2.0.
I missed out few piece of coding (Closing filestream before deleting a file) but no prob in dot net framwork 2.0.I am able to delete a file that am creating in local drive
but there was no error when i was testing.now i installed in another PC.that pc contains al framework from 1.1 to 4.0
Now an error occurs in that new pc that has all frameworks. (File is being used by another process Error)
Will it consider the latest framework(4.0) even thogh we did an app using Dot net framework 2.0?