It's not only Windows Vista Service Pack 1 that isn't ready for general consumer availability. Some of the updates released on February 12, 2008, as a part of the Microsoft monthly patch cycle, have managed to effectively kill Windows Vista. Users are reporting that, following the introduction of the February 12 updates, Vista gets stuck at the finalization of the deployment of the updates displaying the message "Configuring Updates Stage 3 of 3 0% completes" and then entering an infinite reboot loop. And there is absolutely no way out for the end users, because canceling the configuration process of the updates is a move equivalent to losing access to the operating system entirely. This will even happen in Safe Mode.
Microsoft has yet to officially respond to the issue, or to provide a resolve or at least a workaround. However, it does seem at this point that there is an issue with the deployment of the pre-requisite updates necessary for the smooth installation of Windows Vista SP1. Namely, the problem resides in the Vista installation software. The fact of the matter is that end users will have to first update the Vista installation software and only then deploy the remaining February 12 updates and only at the end Vista SP1 RTM.
If you are stuck watching the "Configuring Updates Stage 3 of 3 0% complete Do not turn off Computer" and in the endless reboot loop, then stop the cycle and boot from the Vista media. You will need to "Repair your computer," so select your Vista installation and restore it to a point before the deployment of the updates. After gaining back access to your operating system, you will have to install the service stack update, namely Update for Windows Vista (KB937287). Deploy this update before any other on your Vista, and only then install the rest. At this point in time, you should experience no more problems.
"Update 937287 is a prerequisite package that contains updates to the Windows Vista installation software. The installation software is the component that handles the installation and the removal of software updates, language packs, optional Windows features, and service packs. Update 937287 is necessary to successfully install and to remove Windows Vista SP1 on all versions of Windows Vista," Microsoft revealed.