@Peter
We think that the problem is on the side of Thunderbird .... do to the fact, that it is possible to get e-mails by pop3 when we use an other computer or an other Thunderbird profile, we think that Thunderbird will not accept IMAP and POP in one profile for the same e-mail account.
We have tested to try this on 2 computers in the same time and we can use both protocols.
The fact that TB says that the password is wrong is a bug. TB will only not that we install 2 times the same account.
The people from the TB Forums has tried to say to us, that we are crazy if we install one account as pop3 and IMAP but they do not say if this is possible or not.
It seems also, that we are the only users who do not use the e-mail only for "Twitter-messages" and other unserious issues.
Still in the beginning of the IMAP protocoll we have stated that there are a lot of very stupid bugs in the IMAP system.
We accept only since about 5 Years that our customers use IMAP insteat of POP3. But this was not a good idea.
The problem is simple: when the server space is not illimited ... IMAP will get in problems due to occupied by SPAM, the Trash space, and the backup. A second issue is the fact, that IMAP download constantely all headers and mails but do not store thease Files on te local Thunderbird.
This will mean, that every time you open Thunderbird, TB must download a lot of things but do not store these Datas. If you want to store the datas, you must download all at new....
If you have a lot of accounts with a lot of e-mails, you must often wait a long time.
For this reasons we had tested a new system of handling: we have set up in the IMAP account filters who move the needed Emails automatically down in local folders.
This works some tiime fine ... the needet mails are moved down in a local folder but if we do not delete every day all the SPAM and not very interesting mails ... we have after x months accounts with xxxxx Mails in the inbox. Often the SPAM Folder is full, it is possible that the SPAM folder is hidden ... An other problem is, that mails needed to accept passwords, comes on the local folder in a false folder and we do not find thease mails ...
For these reasons we had the Idea, that we will create also a pop3 account in TB who will download all the mails older then 10 days.
And this will not work. Probably it will be possible to create a second TB Profile with the POP Version of the accounts ... but this will then create a problem with the files still mouved to the local folders in the IMAP instance.
Now I have fund a new idea: I have set-up a filter ... move all e-mails older then 10 Days in a local folder and an other filter move mails marked with as download also to the local folder. In this way only mails < 10 days stays on the IMAP and the older mails will be on the local computer. (the "local computer" is a Cloud and in this way the TB Files will be accessible from all locations ... on some computers it is also possible to use only local mail clients.
brainstuffch