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I’m unable to send email to employees on CUNY M365.

Since the migration to M365 is happening in phases, it’s likely that you are trying to send email from your local college mailbox to an employee that was migrated to a M365 cloud mailbox. This may result in an “Undeliverable” auto-response the first time you try to email that person after they were migrated.


Here are two options to resolve the issue:

Option 1: Enter the full email address of the employee instead of just the name

Since the person’s name still points to their old local mailbox, enter the complete email address username@brooklyn.cuny.edu to send the message their new mailbox.

Option 2: Update your local address book

To resolve this issue in Outlook, you need to update your local address book as follows: (you only need to do this once for each contact, until your mailbox is migrated to M365)

1. Click the To button in the new email window to search the Global Address List.

2. Find and select the name of the person you are trying to contact — it will likely end with (M365).

3. Press OK to update your local address book with the new contact.

4. Send your message.

Contact the ITS Helpdesk if you are still unable to reach an employee by email after following the steps above.

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