Windows and programs randomly stop responding

[Feldir]

Quite frequently windows or a program will stop responding, locking up my computer. I was running a /verifyonly, and at 30% it stopped. A few minutes later the following error presented itself.

mcagent.exe - Application Error

The instruction at 0xe7bcdcd5 referred to memory at 0x00000000. The memory could not be read.

I've had some issues with video drivers lately, could this be the problem?

 

[Ztruker]

I believe mcagent.exe belongs to McAffee AV. Uninstall McAfee and install Microsoft Security Essentials, see if that resolves the problem.