mup.exe?

Apprently mup.exe has something to do with playing music downloads: http://www.arkkra.com/doc/dosinst.html

Have you checked your system for spyware using a reputable anti-spyware product like Adaware or Spybot Search & Destroy?

If you want to remove the attempt to load mup.exe, you need to check the Startup folder in your profile. If it is not there, you have to exercise great caution - seriously - and run regedit.exe and try to find references to mup.exe. Usually unwanted program loads are hiding under the Run key in HKLM\Software\Microsoft\Windows\CurrenVersion, or HKCU\Software\Microsoft\Windows\CurrenVersion, or HKUsers\.DEFAULT\Software\Microsoft\Windows\CurrenVersion.

1. Take out all PCI cards. Replace the video card (if not on-board).
2. Run RAM test. Download the utility from http://tinyurl.com/qoy4.
3. CHKDSK /R ? Run this from Repair Console or by connecting the HD to a Win2K or XP system. This is to check whether Windows File System got corrupted or not.
4. Run HD diagnostic utility. This is to check whether your HD developed bad sectors or not. If it did, replace the HD.
5. System Restore ? If you can boot to Safe Mode with Command Prompt, run this. Refer to http://tinyurl.com/bz7pu (MS KB304449: How to start the System Restore tool at a command prompt in Windows XP).
6. Test clean install Windows in another HD. This is to make sure that the HW is not the cause. If there is a problem, the cause is either MB or CPU.
7. Reinstall (in-place upgrade or repair install) Windows.
8. Backup data and clean install Windows.

Are you certain it's mup.exe and not mup.sys?

i am wildly guessing that if nothing much has changed a good defrag and file system repair might be the ticket. you will need to run recovery console for that.
did you try picking Last Known Good Configuratin from the f8 boot menu?

That particular file only appears on an AMD M'Board when booting into Safe Mode and appears directly after the Video Driver or at least the AGP driver as I haven't ever tried booting into Safe Mode with a PCI Xpress Video Card fitted.

If you have an AMD based computer I would be looking at the video drivers as your problem.

Col

Here is how to open an "MS-DOS Prompt" window. You may have a shortcut icon called "MS-DOS Prompt" or "Command Prompt". Or, in the Start menu under Programs, you may have "MS-DOS Prompt" or "Command Prompt". If you don't have it in those places, go to the Start menu, then to Run, and tell it to run this:

c:\windows\command.com

In this window you can type commands. After typing a command you always have to hit the "Enter" or "Return" key to make the computer run the command. You can repeat a command by hitting the up arrow key and then "Enter".

"Folder" and "directory" are also two different words for the same thing. From Windows, you are more likely to be familiar with the term "folder", so we will use that. In an MS-DOS Prompt window, you are always "in" some folder. In the lower left of the window, it shows you what folder you are now in. (That is called a "prompt", because it is prompting you to type the next command you want it to do.) The folder name is followed by a ">", so if you are in a folder called c:\mup you will see

C:\MUP>

Some versions of MS-DOS restrict file names to eight characters plus an extension (which is a dot and up to three characters). Also, it may have problems with special characters, such as blanks and punctuation. So when you make file names for the music you write, you may find you need to follow these restrictions.

Installing the Mup exe files
No matter which way you intend to run Mup, you will need mup52dos.exe (unless you are going to compile the program from source, mup52src.exe, which most users will not want to do). And you should download mup52doc.exe, the documentation, which includes the User's Guide.

We suggest you install Mup in a folder called c:\mup. (You can use a different name, but the following examples assume c:\mup.) You can create that folder by using Windows Explorer. Or you can do it from an MS-DOS Prompt window, by typing the command

mkdir c:\mup