Avast blocking Windows 10 1803 from updating

[ptorossian]

Hi, I have 2 computers with the same Avast account. One updated from 1803 to 1903 just fine. The other is blocked.

On the one that's not updating, I've updated Avast to the latest version (19.7.2388 (build 19.6.4546.517)) and updated the virus definitions (190820-4). Windows 10 still says I have to uninstall Avast to continue updating. According to this Avast post: https://support.avast.com/en-ww/article/Antivirus-Windows-10-update it seems that should fix the update problem but it hasn't.

Anyone know how to fix Avast so that I can update Windows 10?

[Pondus]

Have you tried to turn off avast self defence

[DavidR]

@    ptorossian
That article dates from April 2018, so much would have changed at MS and Avast since then.

I have a win10 laptop and I never uninstalled Avast to do a windows update so far

How are you trying to update them ?
My laptop was also still on 1803 until a few days ago, it didn't get 1807 either and had been waiting for 1903, it never came. 

Eventually I got the notice about the feature update to 1903, but it said that my system wasn't ready, but I didn't need to do anything.  It never said what was wrong, eventually I decided to use the Windows Update Assistant and the only precaution I took was to disable the avast self-defence module (as Pondus mentioned) and eventually it did take.

See this topic, https://forum.avast.com/index.php?topic=228890.0 and my post in it https://forum.avast.com/index.php?topic=228890.msg1516315#msg1516315 on what I had to do.

[ptorossian]

Thanks for the suggestion, guys. I tried it but it didn't seem to work for me. I got the same result as last time. I'm not sure if I did it correctly though. Here are the steps I did:

• Right click Avast
• Click Open Avast user interface
• Click Menu -> Settings -> Troubleshooting
• Uncheck Enable Self-Defense checkbox
• Open Windows Update
• Click Fix under "Feature update to Windows 10, version 1903"
• *Installing gets to 25% then a dialog box opens that says "What needs your attention" "Avast Antivirus" "Uninstall this app now because it isn't compatible with Windows 10."

I even disabled all Avast shields and clicked Refresh to see if that'd fix it but it didn't.

[DavidR]

After note 4 in your post:
You should have got an Are you sure full window style notification, did you get that and answer Yes ?

Your note 5 and 6:
I didn't go down that route as I never got to the point that I was offered 1903 so nothing to fix.  Did it ever say what needed fixing ?

Have you tried using the Windows Update Assistant ?
After some hiccups, unrelated to avast that worked for me (having previously disabled the avast self-defence module..

[BWhit]

We have had a few reported instances of this issue being caused by Windows finding an old version of avastui.exe saved somewhere on the hard drive - usually in a sub-folder of C:\Windows.old (a backup folder of Windows created when an older version of Windows is upgraded).

I would recommend searching your hard drive for any copies of avastui.exe. The current version will be found in either C:\Program Files\AVAST Software\Avast or C:\Program Files (x86)\AVAST Software\Avast (unless you chose a custom location to install Avast). Do not delete the file found in either of these folders - doing so will cause major issues your current Avast installation.

Any version located in a different folder should be deleted, which should stop Windows Update recognizing it as incompatible.

[ptorossian]

Thank you so much BWhit! That fixed it. Turns out I had an old version of avast on my older HDD (D drive) that's still connected to my computer. I used that HDD before I upgrade to an SSD (now C drive). My other computer came with an SSD so that's why it update to 1903 just fine; it didn't have a ghost of Avast versions past.

Turns out all I needed to do was rename it to AvastUI-old.exe. Windows must be doing a check in Program Files (it was a short search so I'm guessing it didn't search my whole computer) on all attached drives for AvastUI.exe. I didn't even have to turn off the self defense feature.

[schmidthouse]

Thank you so much BWhit! That fixed it. Turns out I had an old version of avast on my older HDD (D drive) that's still connected to my computer. I used that HDD before I upgrade to an SSD (now C drive). My other computer came with an SSD so that's why it update to 1903 just fine; it didn't have a ghost of Avast versions past.

Turns out all I needed to do was rename it to AvastUI-old.exe. Windows must be doing a check in Program Files (it was a short search so I'm guessing it didn't search my whole computer) on all attached drives for AvastUI.exe. I didn't even have to turn off the self defense feature.

Very interesting as it begs the question, maybe many of users needing/wanting to update from 1803 to 1903 didn't have to "disable self-defense or uninstall Avast given this info from BWhit.

[DavidR]

Thank you so much BWhit! That fixed it. Turns out I had an old version of avast on my older HDD (D drive) that's still connected to my computer. I used that HDD before I upgrade to an SSD (now C drive). My other computer came with an SSD so that's why it update to 1903 just fine; it didn't have a ghost of Avast versions past.

Turns out all I needed to do was rename it to AvastUI-old.exe. Windows must be doing a check in Program Files (it was a short search so I'm guessing it didn't search my whole computer) on all attached drives for AvastUI.exe. I didn't even have to turn off the self defense feature.

Very interesting as it begs the question, maybe many of users needing/wanting to update from 1803 to 1903 didn't have to "disable self-defense or uninstall Avast given this info from BWhit.

Previously I had never disabled/uninstalled avast or the self-defence module.  I disable the self-defence module this time around, given the many posts were this was supposedly an issue.

But I did surprise me that the OS would be looking elsewhere on your drives/partitions for potential problems.  For the most part people have avast installed in the default location not on another partition. 

I would have expected MS to be somewhat smarter and know which AV is installed and active and in what location, after all it is meant monitored by the windows security centre.

[mchain]

Related to what BWhit said, it is another reason to remove an Windows.old folders once you know your new os install is clean and good to go.

[DavidR]

Related to what BWhit said, it is another reason to remove an Windows.old folders once you know your new os install is clean and good to go.

I thought that after 30 days the OS was meant to remove that ?

[BWhit]

@ ptorossian - good to hear it worked for you

@ Schmidthouse - having an old version of the avastui.exe somewhere on the system specifically causes the Windows Update dialog to report "Uninstall this app now because it isn't compatible with Windows 10.". I don't believe I've seen any other users reporting seeing this message on the forum - and I believe the Self-defense module was indeed causing most of these issues. The Self-defense issue should have been resolved now in the 19.7 update:

Some of the other features/fixes in this release:

• We can now automatically shut down your PC after a Full, Targeted, or Custom scan
• Quick Scans can now be added to your custom scans and scheduled for any time you’d like
• Added an option to Enable/Disable QUIC scanning in Settings
• Separating consents for Google Analytics and Jumpshot tracking in Settings
• Fixed issue in explorer scan where toaster was displayed just on the first occasion
• Fixed memory leak in aswStm.sys driver
• Fixed not working mail messages in Mozilla Thunderbird
• Fix of occasional blocking of MS Windows 10 update by self-defense
• Fix of problems with nested virtualization (VBox/VMware)Affected Products and Release Date

@DavidR - yes, the OS is supposed to removed the old.windows folder automatically after 30 days, and does so for the vast majority of users. I'm afraid that I don't know the triggers/conditions that might have prevented the automatic deletion for the minority though.

[rocksteady]

I believe Windows "Disk Clean-up" tool (right click on OS drive) can be used to manually purge old OS files.
But only do this if you have accepeted the new windows feature version happy to forego ability to fall-back to the old version.

[Pako7]

Is it avast or You are trying to update the new os with a usb inserted on the computer? because last time i checked that update only failed on my friends computer when he had a usb inserted , its funny he also blamed Avast up until i came and helped hime out

[bob3160]

,

Is it avast or You are trying to update the new os with a usb inserted on the computer? because last time i checked that update only failed on my friends computer when he had a usb inserted , its funny he also blamed Avast up until i came and helped hime out

There are many reasons an upgrade can fail. In v1809, an attached USB device is one of those reasons.
There are unfortunately many others. In some cases, you may need to totally remove your third party AV.