In Windows Millenium there was a new feature introduced called
System Restore. Windows ME creates backup copies of the essential
system files so they can be restored if they get corrupted.
Sometimes this makes the disinfection difficult since the backup
files can get infected. In those cases Windows will copy the
infected file in the place of the clean one.
This feature can be disabled with the following steps
1. Right-click on the My Computer icon and select Properties
2. In the System Properties windows select the Performance tab
3. Click on File System... button
4. In the Filesystem Properties window select the Troubleshooting tab
5. Check the Disable System Restore checkbox
6. Click Apply button
7. Close the windows using the Close button
7. Click Yes when prompted for reboot
The System Restore feature can be enabled again with the same
steps. At step 5. you have to uncheck the Disable System Restore
checkbox.