None of my Apple devices will accept that my BT password/address is correct when I try to add BT account.
This has been working ok but not now.
Just a couple of things to check to aid anyone who wants to help you. My Apple devices worked fine with the old BT-Yahoo service and they continued to work without a break when BT switched to their new BT service. So there's hope for yours.
First, I guess you are using the Apple Mail app that came preloaded on each Apple device. Is that right?
Second can you tell us what version or versions of IOS you are using. (Run the Settings App, select General and then About. What we want is labelled: Software Version.)
Third please you tell us what exactly you are doing to add an email account and what you see on the screen that tells you the device will not accept your BT password and address.
Lastly I'm sure anyone trying to help would like to know that you have looked at the BT help pages on this subject and done exactly what they say. Here's one page that may be helpful - https://www.bt.com/help/email/updating-your-bt-email-settings. Clicking "iOS Mail" opens a set of instructions for the Apple mail app on Apple devices. It's slightly out of date. On my device (IOS 13.3.1) the SMTP Primary server setting is together with the email settings and not held separately as described so expect your will be the same.
Not going to be much help, I'm afraid. Let's hope someone else will pick this up.
I've seen Apple apps giving error messages that don't describe what really went wrong so I updated my phone to the same software version as yours and tried to find an error that would give the same message. The only way I found to get a result like yours was to give the wrong password.
Have you tried confirming your email and password by going to bt.com/email and logging in to BT's web mail? Just to make sure. Are you able to try setting up the email account using a mail app on a computer? If both of those work then it looks as though there's a problem specific to your device mail app. I suspect the "official" advice would be to try increasingly drastic levels of reset before trying the email again - but that would lose other settings and/or data held on the phone so you might reasonably not want to do it.
By the way I'm curious, you said the email was working before, but you also said you were now trying to add the account. What happened in between to make it necessary to add the account?
Same problem on my actual Mac computer.
I had to unpartition my hard drive, reinstall, etc.
so lost passwords, redo email accounts.
Have now moved all my email accounts off BT now. Too much hassle.
I am having exactly the same problem
Username or password incorrect - error which they are not, certainly not the password
Fine getting email from BT webpage but not from Apple mail on either iPhone or iMac
Suspect this problem is connected to them stopping using Yahoo, was fine before that
Updated the server details in settings as requested - have spent hours trying to sort this
Only one question - I presume my 'username' for this purpose is my BT email address?
Sorry to hear about that. It's a bit drastic, but if yo udon't need to use all the email addresses BT lets you set up then you could consider setting up a new one just to try out with.
Is "username" the email address?
Yes, on my IOS device and iMac the labels Email, Username and Account are used in different places, but all work happily enough when filled in with my complete email address.
The iMac gives lets you fill in the details using the Accounts tab within Mail preferences or with the Internet Accounts panel within System Preferences, which confusingly can also be accessed from the Mail menu within the Mail app. I don't understand this duplication; my impression is that using the Mail preferences is less flaky and seems to give you better control over the server settings. Although my Mail account is working fine, the System Preferences panel says: "Can't connect ..." and asks for the password; the Apple designers have clearly messed it up a bit, but I'm happily ignoring this fault.
It seems that the passwords you put in on the Mac are held in the "Local Items" "keychain". That's not good news because Apple's "keychain" system is one of those great sounding ideas that turned out to be a bit rubbish in practice, though to be fair, it does seem to be less flaky than it used to be. You can find your email passwords in the keychain by opening the Keychain Access utility and searching for the first part of your email address. Their name in my keychain is "com.apple.IMAP.password" and "com.apple.SMTP.password". Shockingly, the utility will actually display the password on screen, though it does require the password you used to log onto the Mac. I mention this because in the past I have tried deleting individual keychain entries or the whole keychain and sometimes that did seem to put Mail back on track. Made me nervous, though and I wouldn't do it unless I was pretty confident of being able to restore the keychains (eg from a backup).
I deleted the keychain entries for BT, after confirming that the passwords were correct on both
Then tried to setup the account again from within Mail, no difference - still the "username or password incorrect" error
Next step to try setting up a new BT account, but all very frustrating
In the end, because still no joy re. the constant Apple error message, I have stopped routing through my gmail accounts to BT.
No longer using BT Mail. Read on Gmail.