I am offline tonight until late.
I do not know if this is any help but this is the full text of what I found on that mup hang -START OF COPY AND PASTE
Sometimes your system will not boot and you may use the F8 boot options menu to boot Safe Mode. Sometimes if you choose
Safe Mode to boot, the last thing you see on the screen when your system hangs is something like:
There is probably nothing wrong with mup.sys but since that is the last thing on the screen it becomes the target for
replacement by many well wishing helpers, but replacing mup.sys is sometimes an involved process and will unlikely
resolve the issue even if you could replace it. But you can certainly try to replace it - somehow.
There is certainly no need to reinstall XP or even do a Repair Install to resolve what is usually a very simple problem.
I would not waste time, energy or effort on trying to replace mup.sys since I have never seen it to be the real problem
in spite of what you see on the screen. It is always the next thing to load that is the real problem.
As a matter of fact, I have resolved these kinds of errors many times and never seen a problem with the actual mup.sys file
(it is not the problem).
Experience and lots of testing says that the keyboard and mouse driver i8042prt.sys:
The i8042prt.sys file is the KB and mouse driver and is usually the next thing to load on most systems (right after mup.sys), so you
should suspect a problem in the are of keyboard and mouse. Especially if they are USB devices.
If your system restarts continuously,choose from the F8 boot options menu:
Disable automatic restart on system failure
This will display the error message that you can't see when the system restarts itself. That is what Windows is supposed
to do when it has a failure - it is supposed to restart automatically. The error you see on the screen has your answer.
You can also choose from the F8 boot options menu:
Last Known Good Configuration
Last Known Good Configuration is the configuration XP saved the last time Windows booted successfully and choosing that option
may allow you to boot successfully to undo (roll back) whatever got your system afflicted in the first place.
If the system boots with Last Known Good Configuration, uninstall (roll back) the afflicted driver update and get the correct
drivers for your system.
Sometimes when booting in Safe Mode the system will take a long time to get past mup.sys so wait a generous amount of
minutes and see if the boot process will continue. Once booted uninstall (roll back) any recent driver updates and continue
troubleshooting any remaining issues.
What do you think the problem is or what do you think might have changed since the last successful boot?
Disconnect all the peripherals except the keyboard starting with USB devices. You are trying to eliminate the device that
is causing your system not to boot.
You only need a keyboard to boot in Safe Mode, so if the system boots with just a keyboard attached roll back any driver updates
and/or start reconnecting peripherals one at a time and rebooting after each one until the system hangs again. The last thing that
was connected is your culprit (or the driver that goes with it).
If you are using a USB keyboard, that may be part of the problem so use just a PS/2 keyboard if possible.
Have you added a new mouse or any wireless keyboard and mouse devices since the last good boot? Unhook everything that is connected
and try booting again.
Have any new external USB drives been added lately? Disconnect them temporarily to see if your system will boot without
I usually see the problem as a USB mouse or keyboard change/update of some kind. Either physical hardware or some recent
update that has occurred since the last good boot. Sometimes even a CD ROM update will cause the failure.
Have you performed any Windows updates since the last successful boot? Microsoft Windows Update will sometimes include
what it thinks are the best updates to some of your device drivers and sometimes they just do not work on some systems.
There is usually no crash dump file created or clues in the Event Log under these conditions since Windows did not get
far enough along in the boot process or sometimes there is no indication on the BSOD what the afflicted driver is. Advice
to "look at" these things on a system that will not boot is difficult to comprehend.
If you still need help, describe your computer make and model, currently attached peripherals and decide in any new keyboard,
mouse, video or network hardware or drivers were installed since the last time the system booted properly.
If yes, you need to boot somehow to uninstall (roll back) the drivers to the last set that worked properly (but first your system needs
to boot of course).
If you are experiencing a Blue Screen of Death (BSOD) the answer to your problem is usually there. If that is the case (a BSOD) with
a Safe Mode boot, or LKGK boot, report back for further guidance on how to relay BSOD information (you did not supply enough).END of copy and paste.
I had already found the first article which suggested that after mup.sys it is the HDD controller and the graphics.
Various articles on Microsoft tech library and elsewhere have suggested entering BIOS and changing the SATA mode from SATA to AHCI or whatever is available in that particular BIOS. I suppose the thinking behind that must be that for some reason Windows can no longer load the HDD controller in SATA mode. Although I would have thought that would be more of an issue on INSTALL/REPAIR install etc.
Amazingly on another site a number of people reported success in pressing ESC immediately the mup.sys entry appeared on Safe mode boot., presumably then skipping load of the next driver.
Edited by Macboatmaster, 09 February 2011 - 12:22 PM.