MacOS
Once the transition has occurred, instructions on configuring your Outlook client can be found here: https://kb.mit.edu/confluence/x/o5PHCQ
Windows 10/11
When you first launch Outlook after your mailbox has been migrated, you should receive an alert that Outlook has been directed to a new server. Click Allow. You should then be prompted to log in through a Touchstone authentication screen using your certificate or Kerberos login:
https://kb.mit.edu/confluence/display/istcontrib/Office+365+Post-Migration+-+Outlook+for+Windows+10
If you do not receive either prompt, and continue to see a pop-up saying that Outlook is unable to connect to the account, first try closing the Outlook app completely and rebooting your PC. If that doesn't cause the prompt to appear, you will need to remove the mail account and add it back. See below for instructions:
1, Remove the account:
2. Add the account back, this time as an Office 365 account:
iOS
Once the mailbox is successfully migrated to Office 365, the Outlook App in your Apple iPhone/iPad should automatically receive new settings telling it to retrieve mail from Office 365. If the settings do not update automatically, instructions on how to update settings manually can be found here: https://kb.mit.edu/confluence/x/mAjSCQ
Android
The native Android Mail application will not work with Modern Authentication (Touchstone). Instead, you'll need to download and configure the Outlook app if you have not done so already. Instructions for setting up Outlook for Android are here:
https://kb.mit.edu/confluence/x/XoGyCQ