C0000005 Fix How Do I Fix A Stop C000021a Error?

How do I fix a Stop c000021a error? - c0000005 fix

My team is the fatal error blue screen of death after an hour with the computer, but you do not know where they go from there. Dr Watson said:

"Exception has occurred:
App: \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\? \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ C: \\ \\ \\ \\ \\ \\ \\ \\ WINDOWS \\ \\ system32 \\ \\ \\ \\ \\ \\ \\ \\ winlogon.exe (pid = 620)
When: 8/27/2009 @ 13:09:02.046
Exception: c0000005) (access violation "

I do not know what to do. Can anyone help? How can I determine which program pid = 620 and how can I solve this problem?

I looked in the help: http://support.microsoft.com/default.asp ...
But do not say how to solve the problem - only how to find the program number.