@igor - unfortunately, I can't persuade Avast to ping my backup copy of hosts, which I have unexcluded (and backed up!!!!!).
... because specific hosts file processing should remove only the affected lines (and not when they point to localhost), as you're suggesting.
It may be that versions after 10.0.2206 did implement proper processing of the hosts file. But as hosts is what I consider to be an essential system file, there's no way I'm taking chances with it, so it will always be excluded from scans of any type. I don't consider I'm taking a huge risk here as K-Meleon is a fault-intolerant browser, so unless a malicious/compromised website is using bog-standard scripting it won't get anywhere.
So I might put this one to bed and allow everyone to get back on topic. If Avast does ping my sacrificial hosts file, I'll put it up on DropBox or something and give youse a tinkle.
Gordon.
