Are the contacts in Thunderbird independent of the email account source?

Yes.

When I eventually remove the "old" email account for each person from Thunderbird, is the address book with that name also going to vanish?

No.

Having said that, it doesn't hurt to export the addressbooks for backup. Knowing how to do it in Thunderbird is time well spent, don't you think?

Great, thank you for the input!

Are the contacts in Thunderbird independent of the email account source?

Short answer yes, unless they are synced from the [provider such as in a google address book and you delete the google account. </blockquote>

A related question, post migration to the new account, one user has 75% of her folders inside an "INBOX" folder that is inside the normal "inbox" folder. So the account looks like myemail@mydomain.com\inbox\inbox I'd like to hear about why this might have happened. I expect the fix is simply to drag the folders from the nested "INBOX" to the parent "inbox"? Yes it is in caps, and in italics, in tbird.

Now can't post a new question here...I'm logged in...no buttons anywhere for posting a new question.

just a guess, as I know nothing of the servers.

In account settings, server settings > advanced Insert the top level inbox folder name exactly as it appears in the folder pane ensuring you match case and any { }[ ] and the like into the IMAP server Directory. For instance for gmail it is [Gmail]. Based on what you have said this would be inbox

The server directory is where the server keeps all mail for the account. In this case it appears to be inbox, but I would expect everyone to share the same needs as it is the same server, but either way. Try it and see what happens.

And that setting might shift how this is displayed in thunderbird; it's not going to change anything on the server, correct?

Have never seen this dialog before, interesting. I will enter "Inbox" which is the top level inbox listing (the nested one is "INBOX"), but only after hearing from you on the next bit... In the same dialog I see "Personal namespace" with "INBOX." listed. I wonder if this is the issue? Should I remove that? Thanks for this tip, really appreciate it.

There are all "server" settings configured by the server admin, but none of them actually changes anything but that is "seen" in Thunderbird. So you could try taking out the inbox entry. If it does not do what you want, just put it back.

My IMAP experience is with the free providers mostly, but the principals are the same. Perhaps the most important setting here is to allow the server to over ride the personal namespace, which I am guessing is not enabled (user changed from default at some time) the default allows Thunderbird to replace user settings with ones detected from the server in the initial capability connection process if the server reports different settings.

Thanks I'll try it out

It didn't seem to alter the whatever@mydomain.com

 Inbox
   folder 1
   folder 2
   INBOX
     folder 3
     folder 4

Arrangement. But it seems I can now move the folders up to the parent Inbox. I did test that before; it seemed locked somehow. But as long as I can move them into the parent Inbox good enough. Oh...but only one folder at a time. There are hundreds.

It didn't seem to alter the whatever@mydomain.com

 Inbox
   folder 1
   folder 2
   INBOX
     folder 3
     folder 4

Arrangement. But it seems I can now move the folders up to the parent Inbox. I did test that before; it seemed locked somehow. But as long as I can move them into the parent Inbox good enough.

Oh...but only one folder at a time. There are hundreds.

And look at that..."INBOX" has reappeared in Personal Namespace.

It didn't seem to alter the whatever@mydomain.com

 Inbox
   folder 1
   folder 2
   INBOX
     folder 3
     folder 4

Arrangement. But it seems I can now move the folders up to the parent Inbox. I did test that before; it seemed locked somehow. But as long as I can move them into the parent Inbox good enough.

Oh...but only one folder at a time. There are hundreds.

And look at that..."INBOX" has reappeared in Personal Namespace.

Hmmm at least in firefox, this message board behaves badly. Edit post loses everything when submitting.

IMAP server Directory as "Inbox" didn't change anything.

have you tried restarting Thunderbird before you do any moving and copying? Sometime that folder pane takes some force updating to the point of deleting the foldertree.json file in the profile folder, but I would expect at least a restart to be needed to force an update.

Thanks again Matt. Yes I restarted thunderbird each time after the changes to the IMAP dir.

There is another user with Thunderbird linked to this account. I can't see how that would have any impact? In any case I can move move folders one by one. Occassionally the folder won't move, but I can recreate a like named folder where it should be and then move the folder contents. But it's a lot of seemingly unnecessary work.

If "INBOX" persists as the personal namespace, it's possible that it is the correct inbox (system) folder on the server and cannot be deleted or altered. I would confirm if that's the case by logging in to your domain's webmail portal and see which one of the two inbox folders is the system folder. I once experienced the same issue after Mailbird created extra Inbox and Junk folders in my Gmail accounts. Cleaning them up via Thunderbird was not going as expected. They wouldn't burge when deleted in Thunderbird until I did it via webmail.

Thank you Stans; just got back to this. The webmail interface (roundcube) shows that it is indeed the content of the folder INBOX that thunderbird shows as a folder inside of the main Inbox. As you point out, the server's native inbox will have to remain. But it's not clear to me what to do about this? Move the folders that are not in the nested INBOX so that they are inside it? Whatever the 'fix' is, it'd be done in webmail, not in tbird, presumably? Interestingly, the folders in the thunderbird main Inbox are found in webmail under the Archive folder.

ping...