Problem with Mouse - Not working

Well , I guess here goes , here's the story ;

I turned on my computer as part of my daily routine. Computer turned on fine , nothing different happened , everything was normal. Well , when I say normal I miss out the part about the mouse.
The mouse is simply not working. It is a standard windows mouse and is quite old. But I dont think that will have any bearing on what is wrong. Anyway , I then switched the mouse for another mouse , which again did'nt work. So , the problem is not the mouse ( I dont beleive ). My initial ideas where that the mouse drivers were gone , I dont know how to check this. Or that a virus had somehow gotten' into my system.
Anyway , using mousekeys is really annoying me now , and I need your help , what could be wrong?

Thanks in advance everyone , and sorry if I have'nt supplied enough information.

 

Here are the troubleshooting steps from a handy guide I have:

1. Check the mouse cable connection to the PC. If you find it loose, connect it and reboot the PC.

2. For a serial mouse, verify that the serial port is enabled in BIOS and that there are no resource conflicts (in device manager, resource tab of mouse properties should say no conflicts)

3. Try a known good mouse.

4. When using Windows 9x, try using a real mode driver loaded in CONFIG.SYS, if this step works, try restorign Windows system files. (XP has the system file checker - insert the installation CD, go to a command prompt and type 'sfc /scannow')

5. If using a PS/2 mouse, try a serial mouse.

Also, if you suspect malware, see this thread.

 

Sorry about that , the mouse is fixed. Sorry about any inconvenience.

I really should'nt have posted , but mouse keys were just irritating me

Sorry again.