If you have a IMAP mail account: You are remotely viewing the folders and emails on the server. You subscribe to see folders. but this only downloads emailsheaders and downloads the emails upon selection to a temp cache for viewig. They are not stored in your profile.

If you also synchronise then a copy of the server folder is downloaded and stored in the Thunderbird Profile, but synchronised folders keep synchronising so that the server and TB folders are the same.

IT does not matter whether you delete emails via Thunderbird or webmail, you are deleting from the same folders. So, if you delete off server and then discover it has been deleted from Thunderbird, everything is working perfectly.

If you want to keep emails in Thunderbird, but delete off server and you use IMAP:

You need to synchronise the folders, then go into offline mode to stop the sychronising. then move or copy email into a suitably named folder in 'Local Folders' account.

Then go back into online mode and delete the emails from the imap account folders.

Local Folders account stores emails in the TB Profile. Emails in Local Folders do not synch with IMAP accounts. However, as these emails are only on your computer you should backup periodically.

• http://kb.mozillazine.org/Profile_backup
• http://kb.mozillazine.org/IMAP_backup

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