I have just run a scan with Avast Home4 and it came up with an infection result - Win32:Adan-155 which had been quarantined. I can’t find any information about it on the Avast website, though. Where should I go for this?
It’s an adware that infects EXE files acording to avast virus information feature.
Personally I don’t waste much time in trying to find out what something was, just that it’s a good detection. You could do a google search for win32:adan this is more likely to reveal something about the Adan family rather than a specific variant like -155.
What is the infected file name, where was it found e.g. (C:\windows\system32\infected-file-name.xxx) ? Check the avast! Log Viewer (right click the avast icon), Warning section, this contains information on all avast detections.
If you wanted to confirm the detection, you could also check the offending/suspect file at: VirusTotal - Multi engine on-line virus scanner I feel virustotal is the better option as it uses the windows version of avast (more packers supported) and there are currently 29 different scanners.
Or Jotti - Multi engine on-line virus scanner if any other scanners here detect them it is less likely to be a false positive. Whichever scanner you use, you can’t do this with the file in the chest, you will need to move it out.
From this you will also see what other AVs call it as there is no standardisation or naming convention for malware, so you will often find different names, you can then search for info on these names (if you like).