Avast WEBforum

Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Topic started by: bobby1981 on March 29, 2011, 04:36:16 AM

Title: After boot scan/start-up screen Windows 'sleeps'
Post by: bobby1981 on March 29, 2011, 04:36:16 AM
As my truncated subject titles says, if I run Avast! with boot scan it runs absolutely fine for the whole duration, however when it proceeds to then continue booting into Windows (7 SP1 x64) I get the trouble.  The log-in screen appears, then the password box vanishes and a few moments later the computer goes into sleep mode.  When I press the power button again the laptop wakes up and I'm back at the log-in screen, where I can log into Windows just fine (although it's very slow loading and I usually restart the computer again for normal speed).  It's got nothing to do with how long my computer's been idle - it ALWAYS does it when it boots into Windows.

Anyone else get this or know of a fix?  It's not a massive deal and I'm sure there's no foul play or anything, but I don't get why sleep mode is activated.  I only really use the boot scan because it seems to scan deeper than the general Windows one.

Edit: Only a theory.  Could it be that sleep mode is 'activated' during the boot scan, but can't actually work until Windows starts?  Thus as soon as Windows proper comes on it's suddenly activated?  That'd be pretty selective sleep mode properties though...

Edit Edit: Huh.  Boot scan scanned 411881 files, Windows scan 247818.  Some difference!
Title: Re: After boot scan/start-up screen Windows 'sleeps'
Post by: igor on March 29, 2011, 10:27:12 AM
First, regarding the difference in counts - I'm sure it's related to different settings of unpacked archives for the scans you're running.
The boot-time scan is "more thorough" in that it scans early during the boot process (so the potential malware might not have started yet, i.e. couldn't have hidden itself), and that it uses a raw disk access (which again might prevent some hiding to succeed). But it certainly isn't able to unpack more archives than the usual scanner engine (slightly on contrary, actually).

As for the sleep... interesting.
You might be basically right - or at least that's the only explanation I can think of right now. To prevent the computer from sleeping during the scan (which was reported a few times in the past), I added a piece of code that tells windows "don't sleep while this process is running". I'm not actually sure if it had any effect, because I don't think we could reproduce the original behavior... but that was the only thing to try.
Now, maybe... the system doesn't activate the sleep during the scan, because of this, but the timers are counting - and as soon as the scanner terminates, they turn the value accumulated during the scan into an "effect".
[If this theory is true, however, the behavior should depend on how long the boot-time scan has been running. I.e. if you let it scan just one folder instead of all your disks, to make the scan very short (not exceeding the sleep timeout) - it shouldn't happen afterwards.]

I can try to reset the counters just before the boot-time scanner exists (in one of the following virus database updates)... whether it will have any effect, no idea.
Title: Re: After boot scan/start-up screen Windows 'sleeps'
Post by: bobby1981 on March 29, 2011, 01:11:36 PM
Rather oddly my Dell Alienware 'AlienSense' software (basically webcam log-in based on your face) 'forgot' my face data this morning for the first time since... well, ever, actually.  It seemed to work fine last night.  Indeed, the only things I did before bed were the Avast! boot scan (which can't be the trouble as I restarted my computer after the 'sleep' issue and it didn't forget it then), and then the Windows scan.  That didn't find any infections though so I'm at a loss why the AlienSense data was forgotten/deleted.  Probably completely unrelated but I thought I'd post it anyhoo.
Title: Re: After boot scan/start-up screen Windows 'sleeps'
Post by: igor on April 02, 2011, 11:07:09 AM
Has anything changed recently?