View Full Version : The dreaded MUP.SYS strikes again

15-05-2004, 12:58 PM
Not that thereís much wrong with MUP.SYS in itself. Itís really quite an innocuous file.

It just happens to be where a lot of computers, mainly with AMD XP+ cpuís and running WinXP Pro (sometime Win2000) happen to crash when loading drivers in safe mode, when they wonít start in normal mode. Also associated is the infamous XP blue screen of death (if you thought Win 98 BSODís were bad, theyíre trivial compared with the XP ones.

I currently have this problem and itís a very tough one to sort out. Maybe the experts on PressF1 can help.

Currently running a dual boot Ė booting into XP home works fine on one partition of 80GB Seagate, XP Pro always crashes on at mup.sys on the other.

Some additional info:
1. Using same HDD but different MB and cpu (although both Athlon XP+) - problem still happens.
2. Stripped all hardware to the minimum (except for modem) - problem still happens.
3. Used chkdsk /f etc from independent OS - problem still happens. Likewise with fixboot.
4. Checked all drives with latest updates of NAV, AGP, Adaware, Spybot and McAfee Stinger, all clean Ė problem still happens.
5. Renamed mup.sys in XP Pro drivers using an independent OS Ė problem still happens (hangs on next driver NDIS.sys in my case).
6. Disabled mup.sys with XP Recovery Console (booting from original XP CD) Ė problem still happens.
7. Checked with Google to see who else had this problem. Lots of people it seems, some appear to have solved it with various (usually different in each case) tweaks and fiddles (like juggling hardware around), but without anyone being clear of just how it worked. What works for some people doesnít for others. An extensive discussion is right here (http://www.annoyances.org/exec/forum/winxp/r1055861869) for instance.
8. As far as I can tell the emerging concensus seems that itís possibly a power supply problem, less likely a RAM problem, and/or possibly a driver update (or non-update) problem. However I donít see why my XP Home works and my XP Pro crashes with the same RAM, same physical HDD and same power supply. Nor can I see at this time how to update some of the drivers if I canít get into the OS. (BTW, if XP Pro uses essentially the same set of drivers as XP Home, that might help matters. But does it??)

Iím reluctant to upgrade my power supply (currently 300W) without clearer evidence that it is the problem.

Iím even more reluctant to reinstall XP Pro because:
1. A lot of posts indicate they have tried this and the problem just recurs.
2. I donít want to face up to downloading some 50MB of updates, patches, service packs and & with my slow dial-up connection Ė I donít have easy access to another download method.
3. Iíd rather not have to reinstall a pile of software thatís currently all set up and works fine, if only I could get into the OS. (Some software, such as Photoshop and Goldwave can easily be copied from OS to OS and (with a couple of minor qualifications) work fine. Others such as MS Office etc. are so deeply rooted into the Registry that they canít feasibly be moved.)

If anyoneís had this problem and/or has a clear idea on what causes it and how to resolve it, Iíd be most appreciative.

Murray P
15-05-2004, 01:30 PM
Pull the modem as well.

Disable USB in BIOS.

See how that goes.

Cheers Murray P

Graham L
15-05-2004, 02:48 PM
Can you slow down your CPU? It might be worth a try. Because PCs are commodity items, subject to vicious competition, items such as memory are "only just fast enough". Faster costs more. Sometimes, they are "nearly fast enough", or "fast enough most of the time". :_|

I'd imagine that XP Home would be slightly less memory-hungry than XP Pro, so it might not load into a particular area of memory.

15-05-2004, 02:52 PM
What type of motherboard is it? VIA chip based? I remember there used to be a problem with VIA chip motherboards and Athlon CPUs. A quick reg key fixes it I think.

15-05-2004, 02:54 PM
Murray P
Thanx for comments, also for helpful reply to previous post on related topic.

Pulled modem and disabled all USB's. Made no difference.

Then disconnected CD drive. Made no difference.

All I have left now for hardware from original crash are:
80GB Seagate
512 RAM
GE Force 440 AGP video card
Power supply.
Floppy drive which is hardly ever used anyway.

That computer is now operating at pretty much the minimum hardware level. But the problem still remains.
(I'm actually posting this from a different machine, but could have done so from the XP Home OS with modem plugged back in.)
Suggests to me that power supply isn't the problem, particularly since XP Home works fine on the same machine even with full hardware operating.

I'm getting a bit low on ideas by this stage.

However, next in line to try is (with the independent OS) to delete all existing drivers from the XP Pro system32 drivers folder, and re-extract the original minimal set of drivers from the XP Pro CD.

If this works I can reinstall the hardware one-by-one with updated drivers if I can get them.

Any views on that one?

Murray P
15-05-2004, 03:24 PM
Do you have onboard graphics you can enable in BIOS. Pull everything off you can except HDD of course.

Can you get your hands on one of the MS update CD's, a kind PF1'er may rip or lend one to you. If so, reinstall XP pro over the top replacing system files back to original default state where choice is given (especially for services). If that gets you back in, applying CD updates will at least get you somwhere towards being patched. I have a few later XP updates that I have burnt for people, not many though as I use win2k, but willing to help.

Another, riskier, otpion is to use a partitioning tool to create a new partition with your free space, if you have enough (or pop another drive in), intsall a fresh copy of XP pro on that then migrate your app's. Some will work some wont and it may not be too different to a freah install as far as time but could be more hassle sorting the apps out but, at least data "could" be saved. Would a Linux distro/tool be safer for that purpose Graham L?

Cheers Murray P

Graham L
15-05-2004, 04:09 PM
A quick look at a few of the Google hits gives me the impression that most of the "fixes" have actually not fixed the problem. They have done something, and the problem has gone away -- for the moment. :_) Rubber chickens would be as effective.

Some have involved changing PCI cards ... this might have accidentally involved moving cards between slots. That is one thing which could alter timings by a small amount Small amounts matter if it's a marginal speed problem. (20 years ago I moved one board in a backplane to the next slot -- 1/2" away -- so I could get a scope probe onto the next board. That was enough to fix the timing problem, and I was looking at microseconds, not nanoseconds.)

It is highly likely to be not the MUP.SYS module. It's just the last thing loaded before the problem happened. (That's borne out by your point 5). ;-) I suppose it might be something as subtle as crossing a boundary in the mamory management system, causing a register switch. These things go too fast. :-(

When you tried a different MB/CPU did you use the same memory?

If the 512 is made up of 2 256M sticks, try removing one. Or if you can use different RAM slots/"banks", try doing that. Or slow the CPU.

15-05-2004, 04:51 PM
>A quick look at a few of the Google hits gives me the impression that most of the "fixes" have actually not fixed the problem. They have done something, and the problem has gone away -- for the moment. :_) Rubber chickens would be as effective.
Seems that way to me too.

>It is highly likely to be not the MUP.SYS module. It's just the last thing loaded before the problem happened.
Agree with that too. Actually I only used mup.sys as a scapegoat coz that happens with most others. The one mine originally stopped on was amdagp.sys, but after I disabled that it then stopped on mup.sys.

>When you tried a different MB/CPU did you use the same memory?
Yes. Its a single 512 and the only one I have. No point in buying another without clearer evidence that's the problem. And I don't have any computer buddies nearby to borrow one from.

Couple more options. I might ghost the Win pro partition onto a WD 120Gb drive that's in the computer now but unconnected. Only been used for data storage and never had an OS on it.
Alternatively I might install the XP Pro onto this drive and play around a bit more. Might get some more clues that way.

But this would mean that I have 4 OS or remnants thereof installed on the machine (1 win98 - now had it, 2 XP Home which both work fine, and one XP pro in a decidedly parlous state which is having the problems.
I don't want all of these darn things. Weep!! How does one scrub all traces of the unwanted ones short of reformatting?

15-05-2004, 04:56 PM
Sorry. Correction!

It would mean I had 5 OS on the one machine.

2 x XPHome both working, 1 x 98 totally stuffed, 2 x XP Pro on ehighly dubious, the other (hopefully) OK.

No doubt Microsoft doesn't like this. I don't like it either. But what is one to do .......??

Terry Porritt
15-05-2004, 06:13 PM
Even though you dont think RAM could be the problem, it may still be a good idea to run Memtest86, it is very searching, and will show up any slight memory flakiness.


15-05-2004, 09:36 PM
Hi Terry Porritt

Thanx for suggestion. I did download memtest a while ago but itz still unused coz I forgot about it.

Will give it a go when I can get back to that problem.

BTW, was it you who said they did a physics degree at London some 40 years ago. Long long time! Did you ever come across my old friend and physics mentor Don Barnes who did a PhD in physics there about that time. Maybe you tutored him, he tutored you, met up for a drink occasionally, or just heard of him? just curious.

Terry Porritt
15-05-2004, 09:43 PM
I was an external student of London University, and only went there to take exams, but I seem to remember the name Don Barnes from DSIR days. I think he left DSIR to set up his own optics business??

16-05-2004, 12:47 AM
Sounds as your XP Pro disk is stuffed, I have just resolved this problem on a new computer I built for a mate.
Every thing was new, AMD 2500 etc. but upon installing XP Pro it would just hang at mup.
I used another copy of XP Pro and bingo installation went fine.

Rob ;\