Hi,
Just a possibility but try and create another administrator account, log in with that and try installation again. Sometimes a user account can give problems. If all works well delete the original account and rename the new one.

Other ideas,

Verify Window’s Files

1. Go “START”, “RUN” type “CMD” Press “OK” or Boot PC into “safe mode with command prompt”
2. Type sfc /scannow (note:- space after sfc)
3. Windows file protection will check your files. Follow any prompts; you may be required to use your XP CD.
4. Re-boot your PC



Clean Boot

1. Go “Start”
2. “Run”
3. Type “msconfig”
4. Click “OK”
5. Click “Services”
6. Check box “Hide all Microsoft services”
7. Click “Disable All”
8. Click “Apply”
9. Click “Restart”
10. System will reboot, Check if problem still exists. (Do not access the internet or open any file you are unsure of as you have no virus protector running.)
11. If problem is fixed, enable the disabled items 1 at a time until you find the one causing the problem. If not fixed, re-enable all and re-boot.

To Repair Windows XP from your XP CD…..

1. Re-start PC with XP CD in drive (Have your serial number handy)
2. As your PC starts press “F12” for boot menu (Or what your PC may ask for)
3. Scroll to and select “boot from CD.”
4. At prompt “Press any key to boot from CD” Press “Any key”
5. In the Windows XP Setup window, Press “Enter” to set up windows XP, (Don’t worry, this is a repair only, not a fresh install.)
6. At next window, Press “F8” to accept license agreement
7. Wait until windows displays your current version of XP and asks “To repair the selected windows XP installation press R”
8. Press “R”
9. Enter serial number when prompted.
10. Wait for files to be copied (PC will indicate 39 mins, it will take a lot less.)
11. When asked to adjust Regional language options, click “Next” as it is still set.
12. PC will re-boot.
13. If you have AVG Free, copy serial number to a file as you will lose it on repair. After repair a window will pop up asking how you want to treat AVG, Click repair and when prompted enter serial number.
14. Check to see if problem still exists.

Thanks, I'll try that. I'm running win 2003 btw.