Microsoft has released a hotfix for Windows 7 and Windows Server 2008 R2. If your Windows computer faces random freezes, or stops responding randomly, you may want to check out this hotfix.
If your computer is running Windows 7 or Windows Server 2008 R2 and it stops responding randomly and even causes your applications or services that are running on the computer stop working correctly, then this condition could occur because of a deadlock condition between the Lsass.exe process, the Redirected Drive Buffering Subsystem (Rdbss.sys) driver, and the Winsock kernel.
It is also possible that you cannot log on to the computer by using the remote desktop connection utility, in such situations.
If you are facing these problems, download and apply the hotfix from KB2265716.
If your Windows freezes or crashes frequently, you may also want to check this !