The delegate has added the mailbox account of Corey Gray to their own Outlook profile. In this example, the manager is Corey Gray. For example, the following screenshot shows an Outlook 2010 profile that has two Exchange accounts. However, although there is no warning message or error, this profile configuration is not supported.

Outlook 2010, Outlook 2013, and Outlook 2016, Outlook 2019, and Outlook for Office 365 let you add your delegate's account to your own profile and lets your delegate add your account to their profile. Scenario 1: The manager and delegate mailboxes are added to the same profile Additionally, this section provides the steps that you can follow to resolve or to work around these issues. This section describes the two scenarios in which unexpected behavior can occur when you use the Outlook feature that lets you add multiple Exchange accounts to the same profile. You manually add another mailbox account, and the Exchange Server 2010 Service Pack 1 (SP1) Auto Mapping feature adds it at the same time.You add both the manager and delegate mailbox accounts in the same Outlook profile.This article describes two distinct scenarios in which this feature can cause unexpected behavior: However, you know the credentials to access the additional Exchange mailbox.

You do not have Full Access permission to the Exchange mailbox.You have Full Access permission to the additional Exchange mailbox.You can add an additional Exchange account if one of the following conditions is true: Microsoft Outlook 2010, Outlook 2013, Outlook 2016, Outlook 2019 and Outlook for Office 365 let you add multiple Microsoft Exchange accounts to the same profile.

Outlook account settings advanced tab