I first discovered (and now only discover) the fact of the DL either by noticing that CIS updated itself or (usually) that while connected to the Internet, I DLed a huge amount of traffic (I can also click on a usage link in my online access manager but that's something I'm not in the habit of doing as I surf). Today, e.g., I logged onto the Net to check emails and view a couple of news web sites. While online, I did not DL any streaming audio/video, no email attachments - just routine lite stuff. When I logged off, my usage was reported at 283 MB!!! I checked CIS and it showed that I was current to 1/18/2012 15:08:03 PM. When I started, my last updated was noted on 1/16/2012 and I had not accomplished a manual update. My bases .cav file is also dated 1/18/2012 with 112855 KB. Does that mean my bases.cav file was updated entirely anew or do incremental updates reset the date as well? I've noticed that incremental updates only range in the few MB range - not hundreds.
Given my bandwidth total, it would appear that not only was the bases.cav updated, it was updated in its entirety twice - all automatically even though I have unchecked every autoupdate option I can find.
I have unchecked ALL instances of automatic updates even though that reduces my functionality. However, with all of the autoupdates unchecked I cannot perform a system scan: CIS gives me an error message telling me it could not update the data base even though I have CIS set to NOT update before scanning in the scanner settings manual update tab. So if I opt to scan with out an update CIS refuses!?
By the way, I have been online now for 30 minutes, read emails, looked at the same news sites I read earlier, read two Comodo forum messages and have used 5.5 MB bandwidth - not the 283 MB I used this afternoon. I would also note that ALL of my programs, including Windows Update, are set to manual update.