In the configuration utility I deselected "load system services" and "load start-up items" (please don't ask why). When I restarted the computer (XP, BTW) the blue bar kept going but the computer did not boot up. I tried to go into safe mode but when I tried a whole list of files appears and then it just stops. Does anyone know what is wrong?

Wait for a bit, some computers take more time to load in Safe Mode. If it fails then select 'Last known good configuration'.

I can't understand why you deselected those services because they are needed for OS Environment.

Welcome to DaniWeb BTW !

If Last known good configuration fails to work.

Try booting into SAFE MODE with Command Prompt.
Once there press CTRL+SHIFT+ESC

This will bring up your task manager

Click File --> Run

reslect system services

From there you should be good to go.
Simply enter "Shutdown -r -t 05"
into your command prompt and your computer will restart.

I tried the safe mode with cmd prompt but after an hour the screen still did not change from the list. It it stuck at the Mup.sys file. I still have to check if the last know good config option works, though.

And thanks for the welcome.

And as for me unselecting the system services, let's just say that I made a bad choice and leave it at that.

Checked the last good config. After 20 minutes the blue bar kept scrolling. Any other suggestions?

Sorry for double post (if it is a problem), couldn't edit other one.

Let me look around for something.

Do you possibly have a jumpdrive that is 512mb or larger?

Just Googled and found lot of issues regarding Safe Mode and Mup.sys, some are solved by changing BIOS setting (Related to Power Management) and some of them are solved by Recovery Console.

@lightninghawk: I do have a 1 Gb USB drive.

@thunderstorm: Could you tell me or give me a link?

There seems to be many solutions but some of them require having the windows CD, which was not given to me when I bought the computer. I am currently seeing if resetting the motherboard (by removing the battery) will work.

That did not work. I am going to search for other solutions, but if you guys have any ideas please share them.

OK...We will try at best, hope any other member helps you.