I'm putting this up since the database is defunct and it's not general knowledge to noobs. If anyone sees any errors please correct them. And please add anything I missed that would also be helpful. When Windows gets damage beyond the ability of Rollback or Restore to repair you can still salvage your installation without having to reinstall all your programs and data. 1). Back up your critical data to CD, ZIP or another hard drive before beginning. (Just in case.) 2a). Boot the computer from your Windows PRO installation disk but hit del, F1 or whatever key your Bios uses to enter the Bios setup as soon as the Bios self test screen comes up. Ideally you should go through and check all of your Bios settings before you continue (but that's a lot of work). 2b). You need to select "restore default settings" from the menu. Some advanced bios settings require that MB driver software be loaded before they will work properly and this might interfere with the Windows installation. Now change the boot device order in the Bios to boot from the CD. It will probably read Floppy 1rst, IDE0 second, maybe CDROM third. Make CDROM 1rst. Note Don't forget to change the boot sequence back to IDE0 1rst after the install files have been copied form the CD to the HD. 2c). Select Save the changes and Exit. Now reboot again with the Windows CD still in the drive. 3). Windows will load from the CD and you will be asked if you want to repair the existing installation. SAY NO! 4). Select the option to Install Windows. (Sounds like a mistake but keep going.) 5). You will be prompted again if you want to repair the existing installation. Say YES this time. Windows will rebuild your installation without destroying everything else. 6). You will now need to run all the windows updates. Make sure you load any MB drivers required before doing the Windows updates. 7). Now you can go back to bios and turn on any advanced settings you want active like UDMA HD access, SMART HD monitoring, Fast RAM settings, DUAL DDR support, etc. Done.