Virus Scan Advice

I use Avast anti- virus and have found a number of viruses on my computer through the years. Now I'm wondering how many I might have missed?

I don't remember if it does it every time but, after doing a full system scan, if Avast finds a virus it often recommends restarting the computer and scanning on startup- a boot scan. Some time ago I went ahead and followed their advice only to cancel it after a few minutes. It took too long.

Yesterday, after the old Win32.Adware virus was found, it advised me again to do a boot scan. Since I had time, I went ahead with it, not really expecting anything to be found. Nope. All kinds of stuff in there.

I kept checking on the progress, but was getting bored with it after about ten minutes. Boot scans take longer as they're slower and more deliberate. I was about to cancel again when it found another virus- the same kind it had already found in the earlier scan. It then gives you a bunch of options for dealing with it. I chose Fix Automatically, or whatever that option was. I realized later I should have chose Fix All Automatically so I wouldn't have to sit there and do it over again.

It kept on going, eventually finding six other different viruses. After a while it stalled on yet another one. I can't recall the message but something about a file being corrupted and it couldn't deal with it. At that point, since it didn't seem to be scanning anymore, I cancelled the scan and downloaded Malwarebytes which is supposed to be able to get rid of that last one. The others were all sent to the virus chest where they can't do any harm.

Funny thing was, I had no idea anything might be wrong with the computer aside from one small thing I don't think was related to any virus. But that was enough to remind me to run a scan again. I'm wondering if maybe I should just do the boot scan instead of the standard full system scan from now on?

If you've been ignoring boot scan prompts, I advise following their advice.

Update: Installed and ran Malwarebytes as it's supposed to be able to get rid of the Hupigon-ONX trojan- seems like a bad one from its description. Malwarebytes didn't find it but came up with three other suspicious files. I think that happened when I used Malwarebytes before. They're quarantined and I can always bring them back if something isn't working right.