The proper way to do it would have been to create a new account for the new server. That would have avoided the side effects you have experienced.

I'm just wondering if I should do something about this or leave everything as it is now?

As long as everything works I'd probably leave it as is. But that's up to you.

Has this something to do with the DNS records...?

No, it has not.

Many thanks Christ1, very good to know for potential future needs.

I get it now; the previous times a webhost has taken care of all transferring and previously I've transferred everything as a whole — domain, website, and emails — so they of course have done what you suggested in your reply.

But this time I purchased email hosting separately, and started with copying the contents of my email accounts – I had asked their support about the best way to proceed in my case but from their replies I didn't understand that there would have been a "proper way". Oh well, next time.

That said, in case I would want to change the directory (i.e. create a new one), what should I do?

Thank you!

in case I would want to change the directory (i.e. create a new one), what should I do?

What is the account type - POP or IMAP?

It's IMAP

You can simply create your account as IMAP again in Thunderbird, just make sure to give it a different name as the existing one. Account names need to be unique. Depending on the size of your email archive, it may take a while to download all the messages in case you turn on synchronization for your folders. https://support.mozilla.org/kb/imap-synchronization

Once the newly created account is working properly, you can delete the existing one with the wrong 'Local Directory' name.

Thank you very much again. I think I'll leave everything as it is now as you suggested as I'm not that expert and I don't want to make any unrecoverable mess... Hopefully I'll remember all this if I'll change my email host again in the future!

Cheers

Hi christ1,

I still would like to ask something about this issue:

In your last reply you say "Once the newly created account is working properly, you can delete the existing one with the wrong 'Local Directory' name." — I suppose this applies also to the folders that have been created previously, during the previous email host changes...?

My 'Profiles' folder is currently ridiculously big, and in the 'ImapMail' folder I can see subfolders named with the previous email hosts — can, or should, they be removed?

Or is there some other way to clean it up, removing possible duplicates etc.?

My 'Profiles' folder is currently ridiculously big, and in the 'ImapMail' folder I can see subfolders named with the previous email hosts — can, or should, they be removed?

Subfolders belonging the previous email hosts can be removed as long as they are not referenced anymore by an existing account. I.e. no existing account should use them anymore in the 'Local Directory' setting.

Whether you should remove them or not is entirely up to you. But I guess it would make sense if disk space is a concern.

Prior to deleting anything make sure to create a full backup of your Thunderbird profile folder. https://support.mozilla.org/kb/profiles-where-thunderbird-stores-user-data#w_backing-up-a-profile

Thank you very much again. Just before this last email host change I created a backup of my profile folder so I should have the old stuff if needed.

As to the accounts referencing or not, now I actually don't know if they do or not — I've always kept the same account names (using my email addresses as account names that is; for two separate email addresses).

When I look at the contents of those old email host folders in the 'Profiles' folder, there are .msf files that have been last modified many years ago — do I understand correctly that when a new IMAP folder (with a new host) is created, it also picks up the contents of those old folders and they are thus duplicates?

Uhh what a mess.

do I understand correctly that when a new IMAP folder (with a new host) is created, it also picks up the contents of those old folders and they are thus duplicates?

No, this isn't the way it works. Thunderbird would pick up whatever folders and messages are on the (new) server. If the contents on the new server was the same as the contents in the old folder then you should be good to delete the old folder.