Hi!
I updated v4 to v5 (free edition) last week and mail receiving stooped working.
I use Thunderbird 2.0.0.24 (I also updated it to v3.1) with a POP3 email account.
When clicking “Get mail” it goes, the progress bar is moving, and it stays like that for minutes.
No error message anywhere.
I then turned off the e-mail module in Avast and then it worked again.
I see many others reported similar problems with mail, but no real solution.
Regards,
David