Mark V Winquake/Chadquake crashes on startup

As the subject of this says. after i open any of those sourceports the game opens to a black screen for a couple seconds then crashes.
and the only piece of information i have is this part of the qconsole log:

========= Quake Initialized =========

execing quake.rc
execing default.cfg
couldn’t exec config.cfg

Any help?

1st!

2nd!

Try deleting exec.cfg