Preventing execution of new modules?

Hello. #C++ failed me.
How would I got about preventing execution of code in new modules (injected DLLs, etc.)?

Thanks.

>>11
What I've done sofar is basic anti-hack inside the game executable (uses FindWindow and EnumProcesses etc to find generic hacktools) also fixes patched bytes by checking certain address-ranges which are vulnerable and rewriting original bytes if modified..

Got any good ideas for me? :)