Discrepencies between AntiVir on-access vs on-demand?

DejaVu with my VBA32 issue of less than 50% accuracy with on-access..

In testing today, AntiVir seems to be missing files with on-access, but finding them with on-demand. I have verified all settings, altered settings (w/reboot) to see if anything helps (all files, auto, extensions). Heuristics on/off, and about everything else, it is still missing the files.

For example, you can test this yourself with a simple and harmless "Joke" file.

http://www.rjlsoftware.com/software/entertainment/showhide/download.shtml
(note, this is NOT a malicious file, but many AV's detect it as a joke)

AntiVir completely misses it on-access, but finds in on-demand.

Whats going on here? On-access vs on-demand discrepencies are the main reason I switched FROM VBA32, and to discover what appears to be the same thing with AntiVir?

 

I <think> I know what the problem is.

AntiVir is only scanning on-access with the primary databases, and leaving the secondary (Jokes/etc) as on-demand only. If this is the case, I am not too happy about it. I think all databases should be included in all measures of program operation. However I cannot fully verify these findings (yet).

In otherwords:

On-Access: Adware, Dialer, Double Extensions, Phishing, Backdoor-Client.

On-Demand: Adware, Dialer, Double Extensions, Phishing, Backdoor-Client, Jokes, Games, Security Privacy Risk, Unusual Runtime Tools

Again, pure speculation at this point, I haven't fully tested why it is ignoring things it shouldn't be. ;-)

 

Could it have anything to do with the file extensions? I notice that in the default settings, the on-demand scanner has different settings for which files to scan than the on-access scanner.

 

I noticed few weeks back Antivir was detecting WinFixer when I tried to download it. BUT after recent version update it is not dtecting during download but detect when I try to open the file after download. I have all settings kept max.

 

It is not my settings. I have tried *EVERY* variation of settings, including a reboot after changes, and this issue is still present.

 

My AntiVir detects that file on access and on demand.

Did you unpack the zip? The on-access guard does not unpack archives (which is good imho).

 

Bah, I must be on crack tonight.. I didn't even notice that the EXE version of the file was a self extracting archive. I assumed it was just an executable file that was being missed. Apparently it is SUPPOSED to miss compressed files of all type.

It is late, its been a long day, I should have figured that out.

Disregard, all systems normal. LOL