If you have a trojan horse virus, is that bad?

i don't want to buy an antivirus thing

If you have a trojan horse virus, is that bad?virus scan

Very bad

Free - For starters, download, update and run a full scan using SuperAntiSpyware (SAS) http://www.superantispyware.com/

SAS is an exceptionally easy to use application that will remove the majority of difficult Trojans and Worms, not just the easy ones. In addition it has the ability to remove Vundo and Smitfraud infections. SAS can lock your home page to prevent browser hi-jacking attempts.

If possible it is recommended that you load SAS in normal mode but run it in Safe Mode. Safe Mode can be started by continually pressing F8 during the boot sequence. If you are badly infected you might need to run SAS more than once to help clean your system. Afterwards if the only infections now being shown are in System Restore, once you are completely satisfied that you can boot normally, you can either delete the infected restore points manually, or temporarily turn off System Restore to purge the files.

Assuming you have some real awkward infections that persist even after trying all the above I suggest you download a dedicated Smitfraud removal program from:

http://www.afterdawn.com/software/deskto...

If possible run in Safe Mode.

Likewise the dedicated VundoFix:

http://vundofix.atribune.org/