I agree with Jenny.
I would download and install Spybot Search & Destroy, and some other anti-malware software, such as Malwarebytes.
Update both of them, reboot in safe mode (without networking), and run a scan with both tools.
Another program to try is AVG’s Anti-Root Kit program. It has helped me on a few occasions for some real difficult malware removals.
Try GMER also for rootkit detection. Remember to turn off the System Restore option in XP as it may try to restore infected files the next restart. See this McAfee document for information about disabling System Restore on XP.
Many thanks to Jenny, Flame, Carlosdl, Labnuke99., finally my computer gets well.
Here what I have done:
– ZoneAlarm doesn’t provide offline updating virus definition data
– i tried to install Spybot S&D, but the spyware/virus/worm/malware block me to install it. Installation need to access internet, that’s the virus block.
– I tried to install Malwarebytes and it worked, as well as updating the definition data.
– I restarted with safe mode and scanned all hard disks. It found 17 files infected, some cause by Trojan something, others I don’t remember.
– restart, then my computer works well.
Lucky, the virus doesn’t block Malwarebytes.
If you suspect that your computer system has been infected with unknown viruses or spyware programs, you have to immediately backup all the important files stored in your hard disk drive. Then, perform a full system scan of your system to detect possible risks and viruses.