An error occurred working with AutoCAD

Hi Whiz,
I am getting this wired error message while I am working with AutoCAD. This error is bothering me so much, not able to continue with the work. I googled and tried some solutions like reinstalling, and restarting the system and also even I tried to repair it. If the problem is in the card drivers, how do I fix it? Help me to fix the card. Thanks in advance.

FATAL ERROR: Unhandled Access Violation Reading 0x0040 Exception at 401f19beh
