A friend bought me his XP rig to install SP1. Connected it to my cable modem, ran the installation and went to bed.

When I woke up I had a bunch of messenger-spam popups, but the update said that it was complete. I rebooted as instructed... and that was the last time I saw the desktop.

Every boot results in a reboot loop after the XP home screen with the green throbber. Safe mode shows that soon MUP.SYS is the last thing to load. A blue-screen flashes briefly but far to quickly to read. Safe mode command prompt is no better.

The only thing that works is recovery console. Is there any way to use this to turn off automatic rebooting on error?

Prang

Do a search within this forum, there have been soooooooooooooo many posts about it.

probbily you have run an activation crack,or maybe a thingy that you needed to install in save mode.
if you have second comp try downloading winlogon.sys.
use repair console from bootable cd,than replace winlogon.sys in your system32 folder
that should fix the problem.