Is there any way to disable Avast from running the on-access scanner when I click on the Windows Start button?
The time from button click to menu appearance usually lasts several seconds and has made my 3.0Ghz P4 w/1Gb ram XP Pro sp2 mimic the response / performance of a x386 that’s having a really bad day.
I click on the start button and there is no response by avast (no spinning icon). Open the avast on-access scanner (right click avast icon) and click the start button and confirm avast is checking.
Have you recently installed SP2, because there have been issues of things slowing down.
Without more information on your sensitivity settings it is not possible to offer a solution.
In fact, I can’t imagine a way to do this but, why this is happening?
I click on the button and the ‘a’ blue icon do not swirl :
You can change the menu speed with TweakUI applications 
My Standard Shield sensitivity is set to High with Resident Task settings set at their defaults:
Scanner (basic): all boxed checked;
Scanner(Advanced): all boxes checked, including Default extension set - same as the image above in David R’s post;
Blocker: Default extension set checked, No additional extensions listed, “Blocked Operations” - nothing selected, “Allow the operation” radio button selected;
Advanced: no checked boxes, “…list of locations that will not be scanned…” at defaults:
?:\CONFIG.SYS.
?:\MSDOS.SYS
*\PAGEFILE.SYS
*\WIN386.SWP
*SYSTEM.DA?
\USER.DA?
C:\WINDOWS\TEMP*.TMP
C:\WINDOWS\TEMP_AVAST4_\UNP
Also, I’m running Avast Home 4.1.501
As with any other antivirus or security program: as much security you want as much resources are needed. If you do not need this level of protection, just set it to Normal and your system will be less stressed (although, less protected).
My settings are virtually the same, with the exception of:
Blocker: Default extension set checked, No additional extensions listed, "Blocked Operations" - nothing selected, "Allow the operation" radio button selected;
Were mine is set to "Deny the operation,’ my logic being if avast is set to block it, why allow it if you arn’t present.
The same as Technical there is no activity in avast on clicking the start button, there has to be something lse going on.
You didn’t confirm that avast is scanning, does the icon spin or does the number of scaned files increase (in the on-access Standard Shield provider)?
I can’t believe there’s that much diff between Home (which I have) and Pro. I’ve got all resident providers set to high sensitivity, but pressing the Start button gets no reaction from avast on my system.
I’ve got SP2 installed, by the way, if that’s relevant.
Why do you think any difference between Home and Pro will cause this?
I can’t see in this way. I have Pro and, like you, the Start button is ok.
Sorry, Technical, I mis-worded that rather confusingly (what else is new? :-[ ). What I meant was that I didn’t believe that was one of the differences between Home and Pro.
Avast does scan the items when the start menu is clicked. When you click the start button, Windows is accessing some files (most of them in star menu folder[s] under the documents & settings folder), so it is perfectly normal that the on-access scanner reacts. But these (.lnk) files are very small and depending on your system (speed, applications running etc) you may or may not see the ball spinning.
To prevent Avast from scanning those files you can add that folder (or the files) to the exclusion list of Avast.
What happens if you uninstall avast?
If the start menu is still slow then the problem is something else.
Ok, it’s possible. But, take care, exclusion lists must be handled with care and knowleadge. Don’t come back some time after that saying: “Oh, God, I’ve got a virus…” 