GPF in RNAAPP.DLL

Getting various programs, all internet based, crashing with the message:

This program has performed an illegal operation and will be shut down.

When you check details you see the message:

Program has cause a general protection fault in module RNAAPP.DLL

My question is, is there an easy solution to this, or do we have to reinstall all of windows to get at the problem?
The networking drivers have already been reinstalled (both card and protocols).