Thunderbird ceased connections to remote mail

[squarewindow]

About a week ago, my Thunderbird client ceased to make its normal contact with a remote web-mailbox that I have, on my own domain.
The set-up isnt complicated, it's just a normal POP3, the usual login and password, then Thunderbird starts downloading my mail from the domain box.
But one morning, it failed to make contact with the remote server and has refused to do so ever since.
I have not made any changes to my settings, either now or prior to the failure.

I can still access my mail by logging in to the webmail interface, but I'd like to try and solve the problem.
Before I contact my webhost provider, is there anything I should check in Thunderbird first?
My first thought is that the mailbox may have been hacked...I noticed a few more spam than usual this week, so I have changed the password.

Windows7
latest Thunderbird.

[DanRaisch]

If that password was stored for automatic entry by Thunderbird, did you change the password in TB also? Go to TOOLS > OPTIONS >SECURITY > PASSWORDS tab> SAVED PASSWORDS button and there you can delete old passwords. Restart Thunderbird to ensure that the stored password is cleared from memory. The next time you "Get Mail" Thunderbird will ask for the password and you can check the box to remember the value.

Have you tried using the web mail interface and deleting the oldest message in the server inbox that has not yet been downloaded to TB?
How many messages are currently in the Thunderbird Inbox folder?
Do you regularly compact the Thunderbird message folders? http://kb.mozillazine.org/Thunderbird_: ... ng_Folders

[squarewindow]

Hi, many thanks. I did not store the password for auto-entry...Thunderbird usually just put up the box and asked for the password, which I entered manually.....now it doesnt do it at all.
I have checked the mail via the interface and all messages have now been removed by me; there's only one left (there weren't many anyway). I only have three messages currently in my Thunderbird Inbox folder for this account. Compacting; doesnt happen often because I don't get thousands of emails, but at present everything is pretty low in numbers.

[DanRaisch]

Well, it wasn't about the total numbers of messages. Sometimes a message might have a malformed header and Thunderbird has trouble handling that. It can result in the malformed message blocking the download to Thunderbird, not only of that particular message but to the messages that come into the server behind it. TB should handle that more "cleanly" but at this time it doesn't. Deleting the problem message from the server inbox can resolve the blockage.

[squarewindow]

OK, with thanks;...I will run with that at the moment. Off to bed now, I will play around with this further tomorrow, if I can. It's not causing me any serious problems,
but it would be nice to clear it up.