Unmountable_Boot_Volume Error on Windows XP

Ever feel that terror of being unable to boot into Windows XP?

I recently had a problem where my computer kept on looping to the windows boot screen and only making it to mup.sys. Then I would get the BSOD saying it was an Unmountable_Boot_Volume.

Well, here’s the way to fix it:

  • Boot with your original Windows XP CD.
  • When you see the Welcome to setup press the letter R
  • You will get a dos prompt. Type “chkdsk /p” without the quotes and hit enter.
  • Wait a few minutes.
  • Once it’s done, type “fixboot” and hit enter.
  • Hit “Y” and enter at the prompt.
  • Finally, type “exit” and hit enter

The system will now reboot into Windows

If for some reason that doesn’t work for you, you can boot to the recovery console like above and…
Type “chkdsk /r” then enter
When done type “exit” and hit enter.
This will take longer, but the system should boot back into Windows.