trojan...... my laptop keeps restarting

Hi all. Im not that good on these problems but here is whats happening. When i switch on my laptop and enter my password my desktop(vista) loads up then restarts any ideas? ive run avast using the dos version(hope thats correct) and deleted the trojans and infections found. but it still restarts when i enter desktop. im scanning again in safe mode. Whats the best way to find and delete said virus.

Thanks in advance

hey! first welcome to the forum. its sounds like something stops you from entering your computer. i suggest sense i seems like you can.t start your computer properly so that mines you can’t install programs but if you can i can suggest you try MBAB and SAS to scan your computer.

http://filehippo.com/download_malwarebytes_anti_malware/
http://filehippo.com/download_superantispyware/

and if not i suggest you downloading and burning a rescue CD from an clean cd and then boot with it from the infected computer.

http://www.freedrweb.com/livecd/
http://www.free-av.com/en/products/12/avira_antivir_rescue_system.html
http://www.techmixer.com/bitdefender-rescue-cd-with-auto-update-virus-definition-features/

good luck and write back if get any problems.