Hotmail has been regarded stupid for many years, but I saw myself unable to not use hotmail (in thunderbird) due to 10 years of distributing my hotmail adres to about everything.

But recently thunderbird keeps loading all hotmail mails I ever had for unknown reason. The past week I have a copy of all my emails four times now. 4000 mails are pulled in every time. I can only assume the cause is an update or change in the hotmail service, and because hotmail doesn't allow emails being marked as read from a third party like thunderbird, it resends a note to thunderbird that 4000 new mails are waiting to be loaded. This is also not the first time it occurs, have been 2 or 3 times more in the past, but never as much as 4 copies.

Does anyone got a familiar problem? Otherwise I will have to convert everything to gmail. Oh dear.

well this depends on if you are accessing via pop3 or imap?

generally, this should not happen of course. with pop3, i can imagine there is a problem on thunderbirds side, as it can not mark emails as read anyway (at least with the pop3 services I have used (yahoo mail, not recommended).

I use pop3 on hotmail, hotmail afaik doesn't support imap. Even if thunderbird can't mark emails as read with pop3, it shouldn't pull in thousands already downloaded emails on a certain moment. Something from hotmail must notify that all the previously gathered emails are new, perhaps a renewed protocol? Hotmail did something to their servers, something was new. I have another pop3 server account, and something likewise never happened there.