This is more of a statement than a question in case it helps anyone else with the same problem.
I have been experiencing the dreaded IMAP password error for a while but after online chats and calls with BT, plus several days in between calls, the problem has been resolved.
My problem was as follows. I found that I could no longer send emails from my btinternet.com email address using the Mail client on my iPhone and iPad and also using Outlook 365 on my PC. I could receive emails OK, but not send them. I could use webmail OK.
When I tried to send from my iPhone, iPad and Outlook, I would receive a “password incorrect” error message. When I tried reentering my password at this point, it did not solve the problem. Over the course of a few days, I tried changing the password using
and I tried deleting my email account on my Apple devices and then reinstalling it, but all to no avail.
The last thing we (BT and I) tried was doing the two things above once more and then waiting a couple of days without making any further changes. Then today, BT called and asked me to check whether I could yet send emails (I couldn’t) and so then they asked me to retype in my password in the outgoing email server details in Settings on the Apple devices. After doing this I was able to send emails.
BT said this is a known issue. It can take a couple of days for a new password to synchronise on all their servers. So, after a password change you may find it doesn’t work straight away. The problem is worsened if you, as the user, start trying to correct the problem by changing the password again (and again, etc).
If you look through the forum you will find that forum members have long been giving the following advice that if the problem did not resolve its self after a day or two you should stop your devices/email clients from polling for email. Then change your email password and check that you can access your email via webmail (on a browser).
If that worked you should wait at least 30 minutes to an hour and then add the new password to one of your devices/email clients and again check it works. If it does then move onto the next device.
If the above does not resolve the problem forum members were advised that when you change your BT password on an iPhone/iPad/Apple device it may only change for INCOMING mail. To change the outgoing mail password you have to go into Settings; then scroll down to Mail, Contacts, Calendars.
From there select the BT email account and select the account where it is listed under IMAP. You will find the details for the account and can change the password for the Incoming server there, but the outgoing mail server only shows SMTP and mail.btinternet.com
You have to tap on that Primary Server in order to find where the Outgoing password is hidden so you can update it.
Glad to see that the Customer Services are now following advice given on the forum.