Using New Outlook on Windows for personal email, calendar, and contact management
First, sign in directly to https://email.bt.com/mail using the new password and check whether the latest messages appear there. If they do not, the issue is with the BT mailbox, and you will need to contact BT. If they appear online, the problem is limited to Outlook. BT specifically recommends this check when an email app cannot sign in.
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In Outlook, try the following:
- Make sure Work Offline is not enabled under Send/Receive.
- Update the saved password. In classic Outlook, select File > Account Settings > Account Settings, choose the BT account, then open Server Settings and enter the new password.
- Confirm that the account is configured as IMAP, rather than POP. BT recommends IMAP because it synchronizes messages and folders with its server.
- If it still fails, remove the BT account and add it again using Advanced options > Let me set up my account manually > IMAP, using the current BT server settings.
Before removing the account, confirm that all important messages are visible in BT webmail.
Hope this helps, please feel free to give me any updates