I just downloaded Avast (free) to an updated Windows 10 machine. Installed fine, and works fine. But… can no longer launch Windows Update. Uninstalled Avast, Update works fine. Reinstalled, Update won’t launch… it just flashes the update screen and then closes Settings. Any suggestions?
is any previous used AV removed according to vendors instructions using removal tool?
did you reboot 1-2-3 times after install?
go and uninstall avast, on last popup box there is a option to repair
any change?
Yes, used the Avast removal tool. And rebooted more than 3 times after install.
Did the repair. No go.
- Which Avast…? (Free/Pro/IS/Premier)
- Which version…?
- OS…? (32/64 Bit…? - which SP/Build…?)
- Other security related software installed…?
- Which AV(s) did you use before Avast…?
Avast Free - 11.1.2253.
Windows 10/64 Latest Build
Malwarebytes (free)
Defender
You have to disable it on W10…!!
Avast turns off Defender when you install it. 
Update problem can be temporarily fixed by disabling the Avast self protection feature:
http://screencast-o-matic.com/screenshots/u/Lh/1455806913514-81517.png
Avast is aware of the problem and an update is forthcoming.
Turning off self protection made no difference. When I disable Avast, Windows Update works. When I re-enable it, Update is inaccessible and I get an error in Event Viewer which includes this: “Faulting application path: C:\WINDOWS\ImmersiveControlPanel\SystemSettings.exe”.