Gentlemen,

Because one programme may detect what another programme has missed, we are advised to use more than one anti-malware and anti-trojan programme.

I know that I should not run two anti-virus programmes at the same time, but could I have more than one programme installed and use one of them while the others are switched off ? Then switch off the programme that I have been using, and switch on another and use it? To be able to switch from one anti-virus programme to another seems logical, but is it possible ?

Regards, whatapalaver

After I posted, I read the question from RAGNORAK31 and the reply from ACKLAN. Until yesterday I had used a licensed AVG Professional but during the past two weeks the updates were over in a flash - less than two seconds. That made me wonder if there was a fault, so I uninstalled the programme. When I tried to reinstall it there was an error and it would not go in. I contacted AVG technical but could not get an immediate reply so, because I needed to use the internet, and to be on the safe side, I installed the free version of BitDefender. AVG technical replied this morning and it has told me how to overcome the problem. I now have BitDefender, which looks good and is dead simple to use. I like it. But I now have the opportunity to reinstall AVG. That made me wonder if I could have two anti-virus programmes installed, and use only one.

ACKLAN tells RAGNORAK31 "do not install and use two antivirus programmes". It is perhaps a play on words, but does that mean -

1. Do not have two antivirus programmes installed. Even if you never use them.

2. If two anti-virus programmes are installed, do not use them both at the same time.

Regards, whatapalaver

As I have understood it; you can have several AVs installed as long as you disable the resident scanner in all but one.

EDIT: You probably have to do the same for mail scanners and any other automated scans also.

You can indeed have two AVs installed on your hard drive, but only ONE of these should be operating at a time. You must be able to completely "turn off" either (including real time protection or automatic scans).
As long as one is completely dormant, the only thing you have to be careful about is the possibility that the other finds and reports either the other's virus definitions or its quarantined contents.
The safest plan is to rely on one resident AV, and use any of the on-line virus scans.
Regards,
John

The concern with using more than one anti-virus program is due to conflicts that can arise from them both running together in real-time protection mode. Each program will often interpret the activity of the other as a virus and there is a greater chance of them alerting you to "False Positives". Further anti-virus software componets insert themselves into the operating systems core and using more than one can cause instability, crash your computer, slow performance and waste system resources.

While operating in real-time mode, if one AV program finds a virus and then the other AV program also finds the same virus, then both programs will be competing over exclusive rights on dealing with that virus. Each piece of AV software will attempt to seize the offending file and quarantine it. Further, if one AV finds and quarantines the file before the other one does, then you encounter the problem of both AV's wanting to scan each other's zipped or archived files. As jgweed stated this results on each reporting the other's quarantined contents. This can lead to a repetivite cycle of endless alerts that continually warn you that a virus has been found.

I worded the way I did for new users. New user would not install, hence not make the mistake of running two at one time. May be I am too cautious.

I always wondered about the email scanner. Outlook 2003 does some scanning, does it not? Zone Labs Mailfronteer junk filter checks incoming junk and outgoing files as well. How do they play along? Safe to have both? What really is the best strategy here?

I have Bit Defender & AVG installed.
Ewido does a context-menu scan on demand too for me too.
Sorta like AVG's on the same menu, though it's not technically an anti-virus I guess.

Right to the "you can have two anti-virus programmes, but make one inactive with
regards to full-time (resident) protection" ... and any auto-updates also,
I found ... trial & error.

I think what most E-mail applications scan for is SPAM, not viruses; in that case, they would be using filtres (or "rules") strickly within the application, and should not interfer with AVs which are looking for something completely different. Whether several spam filters interfere with each other really depends upon the sequence in which they run, and, I suppose, how they are set up- - - (I am unaquainted with Mailfronteer, so I cannot speak with authority).

My own E-mail strategy is to use the spam filtering of the E-mail provider as the first line of defence, since I don't want to spend time downloading junk into my E-mail client. Not that I get that much from my main E-mail accounts (throw away accounts are another matter, but I do not download ANYTHING from them).
My POP E-mail application (Mozilla) has its own filters (heuristic, as well). I would tend to use these rather than have yet another application doing a redundant job, or my having to remember where I decided (incorrectly) an E-mail was Spam.

Hope this helps,
John

Gentlemen,

Thank you for your advice. Though I would like to have two AV programmes and use only one of them, I do not know how to 'set them up' to do that. Tinkering with the registry does not appeal to me, but if by disabling one of the AVs in the list of startup programmes the other would be free to scan, I could do that.

I particularly liked jgweed's advice so I have scanned with BitDefender and followed that up with a Panda Online scan. While Panda was scanning, I wondered if I should have closed down BitDefender.

AVG Technical has told me how to overcome the installation problem and I have downloaded and saved a new updated AVG programme. I'm still in two minds about installing it. BitDefendar has had some good reviews, and it is free.

Lastly, I use the Zone Alarm Free programme. Should it be disabled when another AV programme scans ?

Regards, whatapalaver

You do not have to muck around in the registry to do what you want, and can manage which AV runs on a start-up menu (I like the one that comes with Spybot in the Tools section). More for use here at BC, I have several AV applications installed, but only really use AVG Free, since I have relied on it for more than three years with very good results.

There is no reason to disable your firewall( Z/A) when you are scanning with any AV application, even those on-line. I would, however, disable any resident AV while using an on-line AV to scan my hard drive.

Hope this helps,
John

Thank you jgweed, and everyone else who has offered advice.

Best wishes. whatapalver

You are welcome. Keep us posted on your progress. Good luck.