I recently used Windows Update to check for and install Windows Vista Service Pack 2. After downloading the update, I was prompted with the usual restart your computer message which I did. After booting up I get to the "Installing Service Pack stage 3 of 3: 0% completion" screen. 5 minutes later of 0% progress my computer flashes to a Blue Screen with an "IRQL less or not equal" error message. The computer then reboots and attempts to install the service pack again with the exact same resulting error in loop. I can boot in safe mode where the installation appears to complete, but in fact nets no result when returning to regular boot.