The password used to access my email account is valid. I followed the guidance provided in the online Mozilla Support page that pertain to my issue.

Thank you AgnesRM for your response! As to the settings I checked. Read this answer in context 👍 1 All Replies (8) Regarding portable - I have not used it so I am not sure how it differs from the desktop version. Either way, take a copy of the Thunderbird portable profile containing all those emails before you try anything! Or keep them in the Local Folders area and not on the server. There is a way to copy messages from TB saved folders to new folders under the IMAP account that should upload the emails to the server if you wanted. If you look at webmail, you'll get an idea how much of that would be available through IMAP.

I am really not sure what happens to all the saved emails you have in folders on your portable app. The one exception is anything you put in Local Folders in TB is only on your Thunderbird device and not on the server. You may also need to 'subscribe' folders in TB to see sub-folders that exist on the server. Folders are 'synced' - changes in either the server (webmail) or TB make the same changes at the other end, deleting from one deletes from both and so on.

With IMAP nothing really downloads - the typical setup shows you the headers of emails but goes back to fetch them from the server when you open/view/reply to a message. The basic idea is with POP email exists on the server until you download it, then it exists on your device in Thunderbird, and the server normally keeps a copy for a limited time before deleting it. Does that means POP is no longer an option? I really recommend you read up on the difference between POP and IMAP. First I am glad you have a good connection now.

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