system
11
I noticed this problem a while ago, and it went away when in Mail Settings I unticked “Scan Newsgroup Messages NNTP”.
But the problem came back
If I disable XFeatures at the server level, which removes the compression, headers can be downloaded.
But it takes a very long time and more space.
So the problem seems to be with Avast blocking access to compressed headers, which we can only resolve by disabling all shields.
Please fix this problem.