I did not import ntoskrnl.lib because I'm trying to do everything in user mode and there I have access to ntdll.dll which contains ntunmapviewofsection. Thats why I started using implib to create an ntdll.dll import library but I couldn't get it to work.
It's good to know that it actually returns the right function pointer. Now I only have to find where the real problem is :) Thank you for your help.
