When you use Microsoft Outlook to connect to a Microsoft Office 365 email account, one or more messages that have the following Subject line may appear in your Inbox:
Outlook Message Manager (profile_name) (KEY: hex_number)
placeholder represents the name of your Outlook messaging profile, and hex_number
represents a hexadecimal string that consists of a combination of numbers and letters from A–F.Note
This issue occurs only when your Outlook messaging profile has the Exchange email account set up to use Online mode.