Your computer may freeze or restart to a black screen that has a "0xc0000034"

Your computer may freeze or restart to a black screen that has a "0xc0000034" error message after you install Windows 7 Service Pack 1 or a Windows Vista service pack

Consider the following scenario. You install Windows 7 Service Pack 1 (SP1) or a Windows Vista service pack on your computer. After the service pack is installed, the computer may freeze or restart. If the computer restarts, you receive an error message that resembles the following on a black screen:
http://support.microsoft.com/kb/975484