XP c-000021a and 0x0000135 error.

Hello,

On a system working for ages.

Had the reboot going on for days. Unattached and reseated everything and now only have main HD in system and a video card.

Finally found 'Disable reboot' but when I did I got the blue screen and c-000021a and 0x0000135 error.

Can't get into Safe mode, stops at mup.sys. I have even changed mup.sys with a new one when I attached it to another box.

I have also usd the XP CD and done the R- chkdsk. It fixed one or more so it said.

It still boots into the XP splash screen and the little blue dots go along for quite a while, then it goes black.

I have looked around but am a little confused with some of the answers.

Is there a definitive one instead of having to reinstall?

Thank you and Merry Christmas and Happy New Year.

oz