Hi all , just lately an Avast popup keeps saying that my Firewall is turned off , i turn it back on but a few days later the same popup appears !!
Am running Win10 with Avast Premier ,any advice appreciated.
Try the following:
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
If you need additional help with the Clean Install, watch this:
https://youtu.be/p-h3myRD51A
Thanks for the advice, will try it out,many thanks. 
You’re welcome. 
Please post back if you need more help and to let us know if this has solved your problem.