I am not a very experienced on computers. though i am taking care of the computers class at my school. on one computer it happened a strange thing which i don't know how to call. in my opinion it is a virus. even when i formatted disk and reinstalled windows xp, the problem repeats.

so here is the explanation of how it shows up:
the computer turns on normally and everything seems ok, but sometimes mouse pointer starts moving chaotically and very fast all around the screen, clicking icons, opening a lot of windows, etc. and even if the REAL mouse is taken away, the mouse pointer on the screen is still moving.

any suggestions of how to fix it? maybe any program that cleans all Hard Disk would help? as i know, there must be some programs that can clean disk much better than windows format so the files couldn't be restored.
well, and first of all - is it a virus or not??

Sounds alot like a problem I once had on the computer of my parents, although I do think when I removed the mouse, the mouse pointer would stop moving. But it was a long time ago, so I'm not completely sure. In this case, the mouse was defect. Maybe you can try switching the mouse with another mouse, and see if the problem persists. Or maybe try the mouse on a different computer, and see if you get the same behaviour. If this doesn't help, maybe the problem could be on the USB, serial or PS/2 bus. Maybe you can try to find a mouse that uses a different bus.

Oh, by the way, the mouse that was causing the problems on the computer of my parents was from the brand 'Trust'.

Hey Kapax, I don't think your problem is a virus, it seems to be something bigger, like this one:
Why is the mouse moving?

yeah Phas, you are definitely right
thanks unstable. i will then first of all try that mouse on different computer, and then try the other mouse on that (broken) computer.

but the thing is that it's pointer is like crazy - moving, clicking everything, though it is not even connected to computer!! argh

this also happens when some serial ports aren't right configured, you should always turn serial enumerate off
some usb devices uses hardware emulator like the FTDI usb-serial port bridge chip
the standard configuration of this driver sometimes causes this jumping behavior

well, the mouse is simple PS/2. and it was working all the time before. the computer is not new, but this problem is really new

maybe some ~random~ windows update modified some configuration -> go check your serial port settings
look at your device manager, if you find 2 mouses try to kill one

this problem could also be found in the google groups

that was the most useful advice i heard!! thank you. i will definitely try it