Avast WEBforum

Avast Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Topic started by: L551 on September 12, 2019, 08:57:29 AM

Title: Uninstalling Avast = Failure to boot Windows 10
Post by: L551 on September 12, 2019, 08:57:29 AM
So, I am having a rather odd issue with my PC. If I uninstall avast and reboot, Windows 10 will no longer boot and will instantly crash as soon as it tries to load.

I had to do a system restore to back to when Avast was still installed to be able to boot again. Attempting to uninstall Avast again returns the same non-booting behavior. How do I even begin troubleshooting what is going on here?
Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: Pondus on September 12, 2019, 09:07:38 AM
Tried this ?   https://support.avast.com/en-ww/article/Uninstall-Antivirus-Utility


Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: L551 on September 12, 2019, 09:12:23 AM
Tried this ?   https://support.avast.com/en-ww/article/Uninstall-Antivirus-Utility

I'd love to but I can't even get into Safe Mode when this happens. I can only get to the troubleshooting screen it brings up after failing to boot a few times.

I'm using Avast Pro / Premium, by the way.

I'll try doing a restore again, but then going into safe mode via the login screen tomorrow and see if avastclear works where the uninstaller doesn't and report back.
Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: rocksteady on September 12, 2019, 10:55:31 AM
I wonder if your problem is a bit like the one described here:
https://forum.avast.com/index.php?topic=228986.0

Edit: Ah, Maybe not after another read. Ignore that link.
But I am sure I have seen another similar post like the OP's on here recently, but finding it hard to track it down even using search.

You should do an avastclear to fully uninstall Avast, but that does involve safe mode.
Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: schmidthouse on September 12, 2019, 05:35:10 PM
Tried this ?   https://support.avast.com/en-ww/article/Uninstall-Antivirus-Utility

I'd love to but I can't even get into Safe Mode when this happens. I can only get to the troubleshooting screen it brings up after failing to boot a few times.

I'm using Avast Pro / Premium, by the way.

I'll try doing a restore again, but then going into safe mode via the login screen tomorrow and see if avastclear works where the uninstaller doesn't and report back.

To be clear, when using Avastclear.exe you don't go into safe mode first....You simply run the tool in Regular Boot Mode, and it will ask you to allow the tool to take the system into Safe Mode (You click YES) and then it will reboot your system into Safe Mode and do its job in Safe Mode.
Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: L551 on September 12, 2019, 08:38:42 PM
So, I've made some progress. Avastclear was able to get me to boot into normal mode ONCE, but then subsequent reboots would display the same non-booting behavior.

I restored again and re-did Avastclear, but this time took a look around in that one boot to see what might be going on. I noticed that Windows Defender was having trouble starting, and the security section of the settings had a lot of [null] and menus that said that they were not working. Additionally, all the Defender settings were greyed out and unable to be selected.

Seeing this, I ran the DISM and SFC repair commands in Powershell, and afterward rebooted. This time, even without Avast, Windows was able to boot correctly and Defender (and its menus) were again working properly. To test this, I then re-installed Avast and then un-installed it after a reboot. Windows remained working.

I plan to stick with Avast as my antivirus provider, I was just wanting to figure out what the heck was going on with my computer. I don't know if this is going to work for good, but for the time being it appears to be working.
Title: Re: Uninstalling Avast = Failure to boot Windows 10
Post by: Pondus on September 12, 2019, 09:52:02 PM
Quote
.  don't know if this is going to work for good, but for the time being it appears to be working.
Why not do a complete reinstall?.... this will also remove all crap programs that was preinstalled

With win10 you can do that with a few click  >>  https://www.youtube.com/watch?v=OtHZueEZe9s