Forum Discussion
Intermittent connection error with an IMAP mailbox
One of our customers is having an issue with new Outlook where after we set up their email as IMAP (which we host), after a while Outlook would no longer recognize the password. When they went into Settings, it showed a message says "Sign-in is required. Click Sign in to resolve." The customer did that, and the sign in failed, so they closed new Outlook and did something else for a while we investigated.
However, the user came back to the computer a little later, opened Outlook on a lark, and everything was back to normal and they could see all their email again.
Does anyone have any idea of what might be causing that? The customer forwarded screenshots of the information they got when they clicked "Troubleshooting Details", but I don't know how helpful that will be for y'all.
1 Reply
You're trying to determine why a hosted IMAP account in new Outlook stopped accepting its password, then recovered without credential changes. That recovery means the banner does not prove the password was wrong; check whether your server rejected authentication or Outlook could not connect.
Confirm the username, IMAP host, port, encryption, and any app-password requirement. At the next occurrence, record the UTC time, preserve Troubleshooting Details, test webmail, and review the mailbox’s IMAP authentication logs for that timestamp. If webmail works and the server shows no rejected login, capture a new Outlook network trace or use Help > Get Diagnostics before restarting Outlook.
If server logs reject authentication, correct the credential or app-password policy. If they show successful authentication, remove and re-add the account under Settings > Accounts > Your accounts, then give Microsoft Support the details, trace, and timestamp. Without those logs, the exact cause cannot be determined confidently.
