I cannot connect my main Exchange email to Outlook for business

Question

I have recently obtained a business account for O365 and in setting this up on a new MAC laptop I have encountered the following issues:

I created the account and log into O365 business using a domain email ******@domain.co.uk. I have not set it up in IONOS as an exchange email and I have been able to add it to the account as IMAP and it has brought in the email history. When I try adding my actual Exchange email address, set up through IONOS, ******@domain.co.uk, it wants me to log into Microsoft at the end of the process and then it shows up on the account as a kind of separate alias account using the login email address ******@domain.co.uk. Not only has it changed the email address that I want to connect, but it doesn't bring in any history anyway. It's as if it's been set up as a completely different email account.

For the life of me I cannot persuade Outlook to connect to ******@domain.co.uk at all. Help!

Aly

Answer 1

Hi @Alyson Rainey

Thank you for posting your question in the Q&A Forum.

The issue you’re seeing happens because both your Microsoft 365 Business account and your IONOS Exchange mailbox use the same email address. Outlook for Mac therefore signs you into Microsoft 365 automatically, creating an empty profile instead of connecting to your actual IONOS mailbox.

To connect the correct Exchange mailbox, please follow these steps:

1. Switch to Legacy Outlook

• Open Outlook.
• In the Outlook menu and select "Revert to Legacy Outlook".
• Outlook will restart in the Legacy version.

2. Add the IONOS mailbox manually

• Go to Tools > Accounts.
• Select (+) icon > Add Account.
• Enter your email address.

If Outlook redirects you to a Microsoft sign-in page:

• Do not complete the Microsoft 365 sign-in. Look for an option to configure the account manually or select a different account type.
• Choose Exchange as the account type (not Microsoft 365).
• Enter your IONOS server details (Server, Username, Password).
• If you see an option related to syncing with Microsoft Cloud, make sure it is disabled.

Outlook is currently connecting to your Microsoft 365 mailbox, which is empty. Manually selecting Exchange ensures Outlook connects directly to the IONOS server where your mailbox data is stored.

If the setup continues to redirect automatically or if you see any specific error messages, please let us know so we can investigate your DNS or Autodiscover routing further.

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