Windows Updates and Service Packs
Windows XP SP3 and Windows Vista SP1 were famous for causing computers to reboot at desktop loading screens. The easiest solution for this problem is to download the latest Windows Updates for your system. Microsoft addressed the reboot problem shortly after the service packs were released. Not all users experienced the problem, but many did.
If you cannot boot into Safe Mode to download the latest updates, you may need to repair your system using your original installation disk. Insert your Windows operating system disk into your disk drive during the boot process. Boot from the CD when prompted. If you are not prompted, press “F12" to view boot options. Select “CD-ROM" from the options screen.
Press “Enter" when the first set of options appears. Do not choose to repair your system at this point. Press “F8" to agree to the EULA, or user agreement. Press “R" when the next screen appears to repair your operating system. The system files that were changed or added during the faulty updates will be deleted. No other files are deleted during this process.
Once your computer restarts, follow the prompts in the GUI screen to set up options such as region, time zone and network settings. As this is a repair and not an installation, accept the defaults by pressing “Next" on each screen. Once the repair is complete, you will arrive back at your desktop screen. You may be prompted to enter your product key, which can be found on your disk’s packaging.
Disable Windows Automatic Updates by going to “Start," “Control Panel" and selecting “Automatic Updates." Choose “Notify me but don’t download or install them." You can manually download updates, but most users forget to do so without the notification. You can also download updates by visiting Microsoft Update or Windows Update. Choose the “Custom" option to prevent downloading faulty updates. Uncheck the boxes beside updates, such as Windows XP SP3 or Windows Vista SP1, before downloading and installing updates.