Do you use a Pop or an IMAP mail account?

If Pop mail account:

I note that you have 'deleted items re-appearing'. This indicates that there may be some corruption. Usually, this occurs if you have not been compacting folders on a regular basis. Sort out this issue first.

The Inbox folder should be used as an Inbox for incoming mail and not as a general storage.

So, make a backup first if you have not already created one. You should be making regular backups. http://kb.mozillazine.org/Profile_backup

Create some folders to organise mail and move emails from Inbox into those folders.

When the Inbox is empty compact the folder. Right click on folder and select 'compact'.

Then with the Trash/Deleted folder and the Junk folder, right click and choose 'Empty Deleted' or 'Empty Junk' as apppropriate. Then right click on folder and choose 'compact'.

Info on how to maintain a healthy Thunderbird. http://kb.mozillazine.org/Keep_it_working_-_Thunderbird

Info on compacting, what it does and why it is important. http://kb.mozillazine.org/Compacting_folders

re: 'mailbox exceeded' This is a message from the server. If you have a pop mail account what settings are selected?

Tools > Account Settings > Server Settings for the mail account

Is 'Leave messages on server' selected? If yes, what have you got selected to deal with the copies on the server?

'For at most eg 14 days' and 'Until I delete them'. Do you have these selected? If no, then select them and click on OK to save changes.

This should prevent a build up of emails on the server.

Login to your account via webmail. Check your quota and delete messages if needed.

Thanks. I've been in dialog w/ my provider, deleted a bunch off the server. I'll now put your other recommendations into practice. I had no idea I needed to do this sort of culling, hadn't had a problem until now. Well, a couple months ago, but I didn't get the significance, nor the correct instructions. Thanks so much for your prompt response. Wish I could get the same from Yahoo, where Ive been having log-in issues for a month+. Grateful to you. :-)

I'm on a POP acct. I was on phone w/ my provider, deleted much of the mail from server. I was assured it would remain on my computer. But it's gone. Including at least 2 folders, unansere I hadn't deleted from server. When I got back to my IP, I was told that this was a TB problem, that the mail should have remained on my computer.

6-9 months ago I lost all my mail and addresses in my final, and finally successful, attempt to upgrade from TB 3.1. There was apparently something corrupt in my profile, I'd had a dialog w/ another TB expert for many weeks to get this upgrade to work. In the end I had to make a new profile but have never been able to recover my lost info. I thought profile-switcher add-on would work, but it needs the old version to recover info. I did, in fact, try again by re-loading the old version, but still never got to my old info. I can only say, it's a good thing I'm not involved in anything critically important. As it is, I've lost addresses, and in this most recent episode, drafts, receipts, inbox. I can only call this 'letting go'. :-(

re 'I was assured it would remain on my computer.' If you have a Pop mail account, the emails should be on your computer, but that assumes you have downloaded them first. If they were not downloaded and you delete off the server, then they cannot be downloaded because they do not exist.

re: lost old emails..recent episode, drafts, receipts, inbox. check this setting:

'Tools' > 'Account Settings' > 'Disc Space' for the account

• select 'don't delete any messages'
• select 'Always keep starred messages'
• click on OK to save changes

If you have a setting in 'Disc Space' that chooses to delete messages, then they are deleted off both your computer and the server. So, you would only use this to perform a massive deletion to remove old emails you really do not want. Note: starred messages would not be removed if that option is selected and those emails have been 'starred'.

re: Dr. Web Light:

If your anti-virus software program detected something, it may have quarantined the entire file.

Pop mail accounts download from server Inbox to mail account Inbox on your computer. The emails are not stored as individual files. They are stored in an mbox file, one email after the other in the order they were downloaded. So, whilst you see eg: an Inbox folder in the Thunderbird Folder Pane, it is in reality a 'file'. when the anti-virus software detected a problem, it may not have realised how the file works; it could not single out a section of the file (the actual email) and so quarantined the entire file.

I do not know what you have set Dr. Web Light to do with those files. If they deleted the file then all is lost. If you can locate the quarantined file, you may be able to return it back to it's location in Thunderbird. Then move emails to appropriate folders as discussed previously. You could then right click on email and save as to a newly created folder on desktop. These emails are then stored as individual .eml files. Run the Dr. Web Light software on that New folder containing the .eml files and the software will detect which one is causing the problem. then you know which one you need to delete in Thunderbird.

As some anti-virus software has this issue with quarantining whole folder (file) of emails, some people choose not to scan Thunderbird files. This is also a good reason why the need to perform backups, because your computer is the only place they are stored once off the server.