OK, I noticed this some time ago but thought I had done something wrong. Now just watched it happen and it was not me. Sometimes my emails are disappearing, not all emails just some of them. It appears that the entire 'thread' of emails from a sender will be deleted also, including any responses I may have sent. It appears to be happening when the folders are compacted. I compact at least once per day. Today I had received an email that I had not yet opened. When prompted to compact, I did, and then the email was gone, nowhere to be found. I am using IMAP on all my accounts and this was the first version of TB that I used IMAP with. Could this be the problem? Should I revert to POP3? I use TB daily for business and cannot take a chance on missing email. I have had complaints from customers that they are not receiving emails I send, a lot recently, and now I am wondering if it is TB. Have been a user since version 1.X, but I am not really liking TB3 so far: it just seems less stable than before. BTW, my current version is 3.0.2 (Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.8) Gecko/20100216 Lightning/1.0b2pre Thunderbird/3.0.2) and I am running the portable version. Any help is appreciated as I have to do something quickly.
this is not so simple. IMAP means, that mails are not kept normally inside your Thunderbird, but are only on the server. Well ,yes , you can make extra local copy of the mails of interest, but in general you will have them on the server and all you are seeing on the TB, is just kind of 'live' watching the contents of the server, something like watching a website in a browser or so.
The IMAP mail system has many features which were not possible with POP, so in fact mails can be deleted from the server not by your action, but by some activities of the server itself, settings, spamfiltering etc. There are features that allow the sender to cancel the mails himself sometimes too.
So compacting has actually nothing much to do with the IMAP, you can not compact anything on the server, you are just compacting local folders, those which are really present on your drive. This would be in case of IMAP only copies of mails stored locally.
Otto Sykora
Basel, Switzerland
If this is a Gmail account and you had been on the web to view your email and you archived one message in a thread it will move the whole thread to the "All Mail" folder. I think in Thunderbird if you hit archive it just moves the one selected message. You can move them back from the All Mail folder to the inbox too.