After upgrade to W10 from W7, Avast background service not starting

[REDACTED]

Since upgrading from W7Pro to W10, the Avast background service does not start automatically. I have checked the service and found it is set to automatic, and it will start if I tell it to through the Avast interface, so I know it is not a service problem.
I used the Avast Uninstall tool to remove Avast, and then reinstalled, and the problem went away temporarily...  (1 day with multiple reboots while I worked out some other W10 bugs) but now it is doing the same again...  not starting on boot so I have to manually start from the Overview screen.
Any suggestions??

[schmidthouse]

Trying a repair on the existing Avast installation may help.
Go to Control Panel/Programs&Features/Avast and select Uninstall/Change
When Avast installation option Screen appears, scroll up/down and select "Repair"
Be sure to reboot when the repair in finished.