I got this answer in the ticket:

We do not recommend you to use more than one security application on one computer. This can cause a lot of conflict.
You should uninstall HitmanPro.

Miroslav Jenšík
Technical Support Engineer
AVAST Software s.r.o.

Where is the service we got in the future from Avast when we had severe problems.
As we see in this forum how many problems there are still in Avast 10.3.2225, I expect this is also a bug in Avast.