Office 365 Email Post Migration Issues and FAQs

1. Apple Mail does not connect after migration.

Once your account is migrated, you will need to remove your account from Apple Mail then add it back.

To remove the account do the follow:

1. Click the Apple icon in top left corner of your screen and select System Preferences.

2. Click Internet Accounts.

3. Select your UofS Account in the left column and click the minus (-) icon in the bottom left corner.

4. Click OK when asked "Are you sure you want to delete the account ''?"

To add the account back, follow the directions on the below setup guide:

2. iOS Mail keeps prompting for password after account was migrated

If the iOS mail app on your device keeps prompting for your email password, check that iOS mail is using the correct username for your Office 365 account.  The correct username should be in the format of your (i.e.

To check the username in iOS mail, do the following:

1. Tap Settings

tap settings

2. Tap Accounts & Passwords

tap accounts and passwords

3. Tap your UofS email account (i.e.

select your uofs email account

4. Tap Account

tap account


5.  If the username shown is just your NSID (i.e. abc123), change the username to your (i.e. and remove from the Domain section as below:

6. Tap Done.

3. Out of Office / Auto-replies not working between migrated users and non-migrated users

During the migration period, when some UofS people have mailboxes on premises and others have Office 365, Out of Office Replies set up in Office 365 will consider UofS users who are still on-premises as "external". You'll need to set up both your internal and external Out of Office reply messages:

1. Log into

2. Click the Gear icon in top right menu bar and select Automatic Replies:

log into owa and click the gear icon

3. Select Send automatic replies

4. Set the time period for the replies

5. Type in your automatic reply message in the text box  

set auto replies

6. Scroll down and put a check in the box for Send automatic reply messages to senders outside my organization

7. Select Send automatic replies to all external senders

8. Make sure you type in your auto reply again in the text area for external senders

set external auto replies

9. Click the OK button at top

click ok

4. Shared mailboxes and calendars (delegates) not accessible

This functionality only works if both parties have their mailboxes in the same location -- either both are on Office 365 (Exchange Online) or both are on-premises. We will be migrating faculty and staff members in batches by unit to minimize the potential for issues between delegate accounts.

5. Outlook for Apple OS and iOS asking for sign-in information after migration

After migration, the Outlook app on your Apple OSX computer, and/or your iOS device, will prompt you for your Office 365 login information, but will auto-fill in the username as your email address.  If you try to login with your email address as the username, that attempt will fail:

autofills email address

In order to access your email account, you will need to type in your username as (i.e., the password for your NSID, and click the Sign In button:

change username to

6. IMAP setups (i.e. Thunderbird) do not connect

After your account is migrated to Office 365, the IMAP server details in your email application will need to be updated to:

General Client Settings

  • Username:
  • Password: NSID Password

IMAP Settings

  • Server name:
  • Port: 993
  • Encryption method: SSL

SMTP Settings

  • Server name:
  • Port: 587
  • Encryption method: TLS or STARTTLS
  • Requires outgoing authentication. Use the same Username and password as above.
  • Normal Password

7. Popup stating that the administrator has made a change that requires you quit and restart Outlook

The first time you open your Outlook application after your account was migrated, you will see a popup that says The Microsoft Exchange administrator has made a change that requires you quit and restart Outlook:

admin popup after migration

You will need to click OK and quit and reopen Outlook.

This message should pop up on Outlook once when your account moved to Office 365, and once for each User, Departmental Mailbox, Room, or Location Calendar you had in shared calendars that moved to Office 365 after you did. You might see the popup several times as users and other accounts finalize over to Office 365.

It's not an error, it's just that Outlook is re-routing where it finds those calendars after accounts move servers.

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