I am running BitDefender and it seems to be picking up stuff that Norton never mentioned. The problem is that BD reports a number of old viruses in my inbox that it says it can't disinfect because they've been archived.
I assume these are all messages that have been deleted (some go back to 2006). So I thought compressing my inbox would get rid of them. But so far BD is still reporting them.
To make things even more confusing, Thunderbird seems to be using both my Application Data/Thunderbird and Application Data/Mozilla (the directory I used before, and which I told Thunderbird to keep using). Both of which were updated today!
Since there are a few hundred of these messages, I would really like to clean things up.
Oh, and my two inboxes are too big to edit! Ideas, tools, etc., would be appreciated, as I'm not sure which questions to ask.
When you say "compressing your inbox", do you mean "compacting your folders"? You should definitely compact your Inbox if you haven't done so already. You can even set Thunderbird to do so automatically Every Once In A While (Preferences > Advanced > Network & Disk Space > "Compact folders when …" — why this isn't already configured this way, I'm not sure). This might not solve your problem, but it's hopefully a starting point.
Classic case for the Tiresome Manual Binary Chop pattern. Remember to back up first. Complexity is something like O(m log n), with m the number of viruses and n the number of messages. You can probably speed things up a bit by dealing only with messages that have attachments.