Windows & Service Pack 1 Update
Posted on March 20, 2011
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
Theres been an issue with the installation of Service Pack 1 on Windows 7.
There is a technical work around found here – I have come across it in a domain environment that uses WSUS.