Microsoft exchange

Good day William, 

Just to gently clarify before going any further, this forum is separate from Microsoft Support. I don’t have the ability to access or investigate individual accounts because this is a user‑to‑user support forum.  

To help me better understand the situation and assist you effectively, could you please share a few details such as:   

1/ What exact error message do you receive when you try to add the Exchange account? 

2/ Are you trying to add the entire Exchange account to Apple Calendar, or are you trying to add only the Exchange calendar? 

3/ Are you using the New Outlook for Mac or the Legacy Outlook for Mac?

This will help me better understand the context and provide more targeted support. Any additional information will help me better understand and support you.    

In the meantime, please try the following: 

Option 1: Confirm the account works online 

Open a private browser window. 

Go to Outlook on the web. 

Sign in with the same Microsoft 365 account. 

Verify that your mailbox and calendar open successfully. 

If you cannot access the mailbox or calendar in Outlook on the web, the issue is related to the account, mailbox, licensing or authentication. 

Option 2: Remove and add the Exchange account again 

Open System Settings and select Internet Accounts. 

Remove the existing Exchange account. 

Restart your Mac. 

Go back to System Settings > Internet Accounts > Add Account. 

Select Microsoft Exchange. 

Enter the full Microsoft 365 email address and complete the Microsoft sign in process, including any MFA prompts. 

After the account is added, confirm that Calendar is enabled for the account. 

Please use the Microsoft sign in window and avoid manually entering server information. 

For detailed information, you can refer to: Use your internet accounts on Mac - Apple Support 

Note: This link is provided for your convenience. It directs you to a third-party website that is not owned, managed, or verified by Microsoft. I cannot guarantee the quality, safety, reliability, or suitability of any content, software, or services available on that site. Please review the information carefully and ensure you understand any potential risks before using it. 

As a workaround, if you need immediate access to your mailbox and calendar, you can add the account to Outlook for Mac. 

If you have any questions, please don’t hesitate to reach out at any time. 

Thank you for your patience and understanding. 

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