What is Mup.sys in Windows XP and why did my computer stop..?

Question

at MUP.SYS when I was booting it in SAFE MODE?

Answer 1

I was have the problem with mup.sys too, and solved after upgrading my BIOS to newer version.

Here another resource about how people solve their problems with mup.sys:
      1. http://www.computing.net/windowsxp/wwwboard/forum/97354.html
      2. http://www.hardwareanalysis.com/content/topic/31874/
      3. http://www.annoyances.org/exec/forum/winxp/t1047532372

Hope this help