On the last couple of scans with Ewido (free scan version ), it has picked up “Hijacker.agent.a” in c:\ documents and settings .Despite removing , it still returns.Is this a serious threat and how can I prevent this recurring ? I have Avast ,Spybot and Ad-aware already installed ,will i have to install Ewido also ? Once again ,grateful for any help and guidance given .
What was the infected file name, where was it found e.g. (C:\windows\system32\infected-file-name.xxx) ?
Have you tried a google search for Hijacker.agent.a, it returns many hits ?
Some of those indicate its association with pop-ups probably adverts (is this the same for you), so if it keeps coming back you would appear to be visiting the same sites and or getting these pop-ups.
You could also check the offending/suspect file at: VirusTotal - Multi engine on-line virus scanner
Or Jotti - Multi engine on-line virus scanner if any other scanners here detect them it is less likely to be a false positive. You can’t do this with the file in the chest, you will need to move it out.
You should send a sample to avast.
If you are not getting a virus warning that you believe is a new, undetected virus then if you can zip and password protect (‘virus’, will do) the suspect file and send it to virus @ avast.com (no spaces), or add the suspect file to the User Files section of the avast chest and send from the chest.
Give a brief outline of the problem (possibly a link to this thread), the fact that you believe it to be a either a new, undetected virus and include the password in the body of the email. Some info on the avast version and VPS number (see about avast {right click avast icon}) will also help.
I would say you should add ewido to your security it works well with avast with no known conflict, the free version after 30 days is an on-demand scan only. This if nothing else would stop you having to go on-line to do a scan.
Thank you once again for the very helpful advice.I have installed Ewido 4.0 and ran same .The system was clean apart from 2 medium tracking cookies. I think the problem was caused by my son who has been using bit torrent sites for downloading . Hopefully this solves the problem,