1. Go to 'QMM Console | Exchange Data | Synchronization Jobs | Mailbox Synchronization | Right Click the configured Exchange Pairing (boxed and highlighted in green in the embedded screenshot below).
2. Click the Properities option and Notification Message.
3. Click 'Custom Message' and Edit (boxed and highlighted in Red)
4. Enter the custom message in the dialog box and click OK.
HTML formatting is supported within the MAgE notification message. Here is an example of how to add a hyperlink to the notification message:
This is how the above message will appear to the end user: