Trend Micro house call and Avast! Cool!

[rasta]

  I use Trend Micro house call (http://housecall.trendmicro.com/) regularly to do an online scan and whenever I use it the little Avast! ball spins like crazy apparenly because Avast! is also scanning some of the files at the same time (On-Access Scanner?).

If this is true, it means the files get scanned twice for the price of one. I think that is the coolest thing since the Eskimos discovered nose rubbing!

The same thing happens when I use http://www.windowsecurity.com/trojanscan/ to scan for Trojans online.

With these two online scans and Avast! in the background, I must have the cleanest system this side of McLean, VA.

Just thought some you might like to know.

[DukeNukem]

As with all anti viruses that have a real time scan engine whenever a file is accessed it will scan it.

BTW do you use any adware/spyware programs, such as spybot search n destroy or Lavasoft Adware SE?

Viruses arent the only threat out there.

 

[DavidR]

It may be advisable to pause the avast on-access scanner after you have safely arrived at the on-line scanner web page.

Two AV scanners running at the same time could cause a conflict (some on-line scanners download a virus pattern file that may trigger your resident AV {Panda's does this}). What/which AV deals with a possible infection if on is found, are both trying to repair/delete/move the infected files? I think you can see the possibilities for conflict.

The main reason you go to an on-line scanner is to provide confirmation (a second opinion) that your system is clean (or not), in which case you wouldn't want your existing AV getting into the mix.

[techie101]

Davids advice is correct.

Some systems will "hang" if Avast runs with Trendmicro.

My Windows98 will stop mid scan on Trend Micro.

You do not need to "double scan" your system.  Use Avast as a primary and the "online" scan as a backup should you run an Avast scan....it shows nothing....but you suspect an infection.  

Depend on ONE AV and use the a manual or online to "confirm" system integrity.

[rasta]

That makes sense to a certain extent but a good anti-virus program will keep the pattern files encrypted on disk and will only decrypt the ones it needs in memory and crean up after itself when it's done.

If the program doesn't do that then it will leave pieces of the pattern file all over the place - in the disk cache in memory, in virtual memory, in pages that get paged in and out, etc. In that case, any other virus scanner or even the same virus scanner will trip on the next memory scan and report all kinds of infection regardless of whether it runs with the online scan or much later. I suspect this is the case with Panda's anti-virus.

I know I don't  need to "double scan" my system. That wasn't my intention. I just think it's a bonus - if unintended - that my system gets scanned against two separate pattern files when I run the online scan.

The  fact that Windows98 stops mid scan on Trend Micro could be due to several unrelated reasons the main one being that it is obsolete.

[Lisandro]

That makes sense to a certain extent but a good anti-virus program will keep the pattern files encrypted on disk and will only decrypt the ones it needs in memory and crean up after itself when it's done.

Panda does not encrypt its files  

If the program doesn't do that then it will leave pieces of the pattern file all over the place - in the disk cache in memory, in virtual memory, in pages that get paged in and out, etc. In that case, any other virus scanner or even the same virus scanner will trip on the next memory scan and report all kinds of infection regardless of whether it runs with the online scan or much later. I suspect this is the case with Panda's anti-virus.

Well, I'm not so sure but, in fact, the whole signature file is not encrypted and will be detected by other antivirus (on-demand or on-line) as infected files  

[rosso_acido]

The  fact that Windows98 stops mid scan on Trend Micro could be due to several unrelated reasons the main one being that it is obsolete.

I wouldn't exactly call it obsolete. It's still a good operating system if you aren't using any demanding graphics rendering programmes and such, and need a simpler way to do things in general - but I really wouldn't like to start a debate on this matter. LOL

Anyway I doubt the scan stopping in the middle has anything to do with Win 98 at all. I'm also using XP on another machine, and it too hangs sometimes when you attempt an online scan with your resident antivirus running...

R.

[DavidR]

That makes sense to a certain extent but a good anti-virus program will keep the pattern files encrypted on disk and will only decrypt the ones it needs in memory and crean up after itself when it's done.

This really hasn't anything to do with encryption and possible false positive hit (after the on-line scan) on unencrypted virus pattern files or whether a good AV program cleans up after its self, but one of conflict.

Two AV scanners running at the same time could cause a conflict (some on-line scanners download a virus pattern file that may trigger your resident AV {Panda's does this}). What/which AV deals with a possible infection if on is found, are both trying to repair/delete/move the infected files? I think you can see the possibilities for conflict.

Which AV will deal with the problem of dual detection of a virus (not unencrypted vpf, but real virus)

We only give advice, it's your system and of course you can do what ever you want.