Access denied when setting AvastSvc.exe Startup type to Manual from Automatic

[Lost Horizon]

Hi,

I just installed Avast Free Antivirus (offline) latest version 24.6 on my new Windows 11 laptop and everything works great except that when I try to set AvastSvc.exe Startup type to "Manual" from the initial/default "Automatic" setting in the services GUI window I got the "Access is denied" error message even though I've already turned off Avast self-defense mechanism - the reason for this is that I work (I'm using my computer) mostly offline so I don't need any kind of virus protection until I'm online.

I looked up the answer on the Internet and I got these 2:

1. modify the registry key "Start" in \HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\<ServiceName> in registry editor
2. run Command Prompt as Administrator:
    sc config "Service Name" start= demand

Can anybody here PLEASE confirm the above if they would work (or NOT). If NOT or if you do have a better solution, PLEASE let me know.

Thank you

[DavidR]

Avast is an on-access antivirus and isn't designed to be an on-demand scanner.

The AvastSvc.exe file is the main avast service and it is most likely you are being stopped from doing this by the Avast Self-Defence module.  If it was easy to do this malware could do it just as easily.  That said the service would be running in the background but not the scanning.

There are options in the right click context menu of the Avast tray icon to temporarily disable Avast.  Outside of this there aren't any options, whilst this may be possible but not something that is wise to even discus in an open forum.

[Lost Horizon]

Hi DavidR,

Thank you for getting back to me. FYI, I did turn off Avast self-defense mechanism before trying to set AvastSvc.exe service Startup type to "Manual". I used to be able to do it on my Windows 7 laptop with Avast 18.8. Like I wrote in my last post, the reason for this is because I work (I'm using my computer) mostly OFFLINE so there is no need for the antivirus to run. Another main reason is that I also want to update the default Microsoft Defender's virus definition files once in a while to keep it up-to-date and with the Avast antivirus running, Microsoft Defender is turned OFF so I can't do that.

[DavidR]

Things have moved on since win7 and Avast 18.8 in terms of protecting the Avast Services.

You should be able to run a Windows Defender on demand scan (?) and also update its virus definitions (presumably it does that before the scan ?).  I have that option disabled on my win10 system.
See attached image, open the Windows Security section - Virus & Threat Protection. You can enable it for Periodic Scanning (I have it disabled/Off).

The real issue is having two active on-access AVs running at the same time as conflict is likely.  Like two dogs and only one bone.