You need to be more specific and/or detailed.

Do you mean to sync the folders with the e-mail server, another device other than the computer running Thunderbird, another e-mail program, or what?

Give details. Explain what you are doing, what happens, and what you want to happen that is different.

I mean to sync the folders with the e-mail server.

Please advise How to sync all folders of an email account (email server) to my thunderbird account on my desktop.

I use this add-on:

https://addons.mozilla.org/en-GB/thunderbird/addon/get-selected-mails/

You just set it to collect messages in all accounts by default.

However I suspect that part of the specification of IMAP is that it won't necessarily get all subfolders. I do find that if I have moved messages into an email account subfolder on one computer, I don't necessarily see this change in another computer until I specifically open that subfolder.

Your reply is not relevant to my query. Please read again:

Please advise How to sync all folders of an email account (email server) to my thunderbird account on my desktop.

It's not related to different email accounts, but related to all folders and subfolders of the single email account.

If you are using IMAP, then the e-mails & folders in Thunderbird under your e-mail address should already be synchronized between Thunderbird and the e-mail server.

Therefore I must assume that you are using POP instead, or you are moving your e-mails to "Local Folders".

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