Clean virus in Windows Installer folder
Case 1: Located Installer folder under windows and delete the file.
Case 2: I used sfc /scannow, after two
scans and two reboots it's working again!
Case 3: Use a new Install and Uninstall Fix it, you can download
and run the tool from here:
Case 4: Use Windows CD to repair.
1. Insert your Windows XP installation CD into your computer's disc drive.
2. Turn on your PC. Your computer will automatically boot from the disc,
bypassing the installer virus.
3. Press "R" to begin a scan. The XP CD will compare your operating system
data to the data on the disc to locate the virus.
4 Click "Repair" when prompted to fix any virus(es) the disc detects. This
will not erase any of your saved data.
5 Eject the disc and restart the computer.
Contact a consultant