Microsoft 365 Post-Migration - Outlook for Windows 10

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Reconnecting Your Mailbox

Once your account has been migrated, reconnect to your mailbox in Outlook for Windows as follows.

1. After migration, the first time you open Outlook you will be notified that you are being redirected to a new server. If you have shared calendars, you may receive several notifications. Choose Allow.
   
   
   
   
2. You're prompted to login via Touchstone Authentication using your MIT Certificate or Kerberos username and password, and DUO. Do so.
   
   
   
   
3. You will receive another redirect notification as you connect to the o365 environment. Check the box to "Always use my response for this server" and click Allow.
   
   
   
   Result: You will be able to send and receive email and use calendaring via the O365 system. If you'd like to confirm it works, send yourself a test message. It may take a minute or so for it to work its way through the system to your inbox.
   

Resource Calendars

If you make changes to resource calendars still present in your Outlook client that were not migrated alongside your mailbox, you will receive the following notification.

In order to remediate this issue, we recommend you:

1. Remove the calendar from your Outlook client
   
2. Restart Outlook
3. Navigate to your Calendar window.
4. Right-click My Calendars and select Add Calendar from address book
5. Set the search to More columns and the "Address Book" field to Global Address List (GAL)
6. Search for the resource's name and press Go
7. Select the calendar and press OK

Note that your account and the resource both need to be on the same server (whether Exchange 13 or M365); otherwise you will not be able to manage permissions or modify, edit, and delete entries on the resource. You will however, be able to see the times the resource is free and busy.

If you are repeatedly prompted for a username and password

1. Run the registry file: MSOAuthForAutodiscover.reg
2. Restart Outlook

See Also

• Microsoft 365 - Email and Calendaring Landing Page
• Modern Authentication Microsoft 365 Email and Calendaring Setup
• [archive:Microsoft 365 Pre-Migration Information]