As far as I am aware, Iran has a history of restricting certain internet activity and web access.
It may or may not be some of the problem you are facing.
I see no reason why Avast would be restricted, but then again, if your country is actively involved
in restricting web access, it could be part of the problem.
Is your access overall affected, or is it just inability to access Avast?
All my best!
Jim
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