I have a trojan horse that won't let me install anti-virus software even in safe

[xdtsztr]

mode? I'm getting a lot of error messages along the lines of:
"system has shut down buggy application"
and "NT_Kernel error 1256"

Also, when I try to download anti-virus software it says "The system administrator has set preferences against the installation of this software." Is there any way to override that?

[Arcadya]

you could have your system scanned online; you just have to install an active x control and it's for free.

[scott p]

You may need to re-install your operating system. Get your system disk, reload everything will save you time and effort then trying to resolve your problem.

[Sly_Old_Mole]

NT_Kernel error 1256 = More than likely Vundo, run vundo removal tool:

http://www.bleepingcomputer.com/forums/topic18610.html

[John_Doh]

look for all the cds that came with your computer makes sure you have the drivers cd and the windows xp or vista cd and reinstall your system or call someone who knows how to reinstall windows.

[dr.bucksnort]

first turn off the system restore in your pc

then run this

http://siri.geekstogo.com/SmitfraudFix.php

[Azrael]

The easiest solution is to download a system rescue disk with embedded antivirus, boot from it, update, scan and clean. One example is a Linux distribution called Vixta (free) .
Google for paid solutions.

[jjvs]

Yeap. That is the nasty one.
Only option you have is to re formate yr hard disc by installing the OS again.
Be sure to copy all needed data using dvd or cd burner as you will loose those permanently by reformatting the hard disc.
Make sure u only use cd/dvd burner to copy data, NEVER connect external hard drive to copy as the virus can goto yr ext hard drive and currupt those contents as well.
Good Luck!