In the new Outlook for Windows, many server settings (especially the incoming mail server) are managed automatically and cannot be edited directly in the same way as in classic Outlook. To change the incoming and outgoing servers for a host email that has moved platforms, use one of these approaches:
- Remove and re-add the account in new Outlook
- Open Outlook and select File.
- Under Account Information, choose the account, then Account Settings.
- Remove the existing account.
- Add the account again using the new server details provided by the host. New Outlook will try to auto-detect and lock in the correct incoming server.
- Use classic Outlook (or Mail in Control Panel) to edit full server settings
If new Outlook still does not let the incoming server be changed, switch to classic Outlook where full server settings can be edited:
- Open Control Panel in Windows.
- Search for and open Mail.
- In Mail Setup – Outlook, select Email Accounts.
- Select the account and choose Change.
- On Change Account, update Incoming mail server and Outgoing mail server to match the new values from the email host.
- Select More Settings → Advanced and verify:
- Incoming server (IMAP/POP) port
- Outgoing server (SMTP) port
- Encryption type (SSL/TLS) as required by the provider.
- Select OK, then Test Account Settings and confirm green check marks.
Alternatively, in classic Outlook itself:
- Open Outlook and select File.
- Under Account Information, select the account and choose Account Settings.
- Select Server Settings and update the login information, server name, port, and authentication for Incoming mail and Outgoing mail.
- Select Next > Done.
If the account still will not authenticate, verify with the host:
- Correct account type (IMAP vs POP)
- Exact incoming/outgoing server names
- Required ports and SSL/TLS settings
- Whether an app password is required (for accounts with two-factor authentication).
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