avast freezes !?

hi,
my browser : firefox 50.0
my firewall : free avast 12.3.2280

since updating to current version, every now and then there’s this problem that looks like avast is frozen.
the tray icon is not not reacting and right-clicking on it won’t open the contextmenue.
shutting down the pc I get the message that avast is not reacting and shut-down process takes about 2-3 minutes.
after restart is working correctly again until … well I don’t know. sometimes internet sessions are without a problem, sometimes it happens right after launching firefox.
a virus is not reported by avast scan
any idea what this could be
thanks in advance for your advice

Welcome to the forum.:slight_smile:
Repair Avast:
Control Panel> Program and Features (Add/remove program)>Select Avast> Select Repair. Reboot when completed
https://www.avast.com/faq.php?article=AVKB204
If Repair doesn’t fix the problem, try the following:
Clean Install of Avast:
https://goo.gl/4Ptzkf