I've been getting this error today when I try to load Q4... it crashes to desktop just after the loading screen, sometimes give this error in the flashing "Error During Initialization" console:

reloading gfx/guis/scrollbar_down.
found DLL in pak file: G:/Games/q4/q4base/game000.pk4/gamex86.dll
copy gamex86.dll to G:/Games/q4/q4base/gamex86.dll
********************
ERROR: couldn't load game dynamic library
********************
Error during initialization
Shutting down OpenGL subsystem
...wglMakeCurrent( NULL, NULL ): success
...deleting GL context: success
...releasing DC: success
...destroying window
...resetting display
...shutting down QGL
...unloading OpenGL DLL

The only changes I made today, that I can think of, is that I installed my new Razer Copperhead mouse. I have the latest drivers and firmware for the mouse, and tried removing it but still could not play.

I uninstalled and reinstalled the game, but still get the same error. Any ideas?