'''Q:''' Are you by any chance using Cox server ? Cox will delete any emails older than 60 days from server if they have not been marked as read. However, I've heard some people report it also occurs if the emails have not been moved out of the Inbox as well. I would say it is better to move them out of the Inbox into other suitable folders for storage. '''Q:''' If no then what server ? '''Q:''' Are you using POP or IMAP mail account ? '''Q:''' Do you have any settings which auto delete after x days ? * Right click on mail account name in Folder pane and select 'SEttings' If POP: * select 'Disc Space' If Imap: * select 'Sychronisation & storage' * select : 'Don't delete any messages' * click on OK '''Q:''' Have you by accident 'Archived' the emails, so they maybe in a different folder - perhaps one you have not subscribed to see (If imap)? If Thunderbird deleted them then they would be in the TRash folder. You can move them back or put them in any folder you prefer. '''Q:''' Does it say anything in the 'Activity Manager' about deleteing? '''Q:''' Have you recently 'Compacted' the Inbox folder? If no then do not do it just yet. * '''Q:''' What happens if right click on Inbox Folder and select 'Properties' * click on 'Repair Folder' button * click on OK '''Q:''' Have you access your webmail account using a browser to see if the emails are still on server?