Hello vladimir.kovalkin,
to help you solve your problem, we need your current Windows version and Avast Cleanup log files.
To get your current Windows version, please type winver in Start->Run menu and click OK, you will see Windows version then.
Regarding Avast Cleanup logs, you can them typically here:
C:\ProgramData\AVAST Software\Avast\log\AvastSvc.log
C:\ProgramData\AVAST Software\Avast\log\GrimeFighter2.log
C:\ProgramData\AVAST Software\Avast\GrimeFighter2\ (the whole folder)
Thank you in advance.
Regards.