The Email Alias Manager for Exchange Add-In is inactive

You have installed the Email Alias Manager for Exchange Outlook Add-In on a user’s computer and it doesn’t appear in Microsoft Outlook, even after you have checked thoroughly:

• There are no errors in the event logs.
• Microsoft .Net Framework 3.5.1 is installed.
• Visual Studio Tools for Office is installed.
• You have Outlook 2013 on Windows 8/8.1. When you close and reopen Outlook, the Add-In is inactive again.

The reason the Add-In is inactive is because the loadbehavior is set to "Unloaded" at start-up. Changing the below key will sort the issue:

HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\Addins\Exclaimer.IdentityManager.Addin

Then, change the DWORD loadbehavior to 3.

Below is a MSDN article on the other values for this DWORD and other information to do with Office Add-Ins:

http://msdn.microsoft.com/en-us/library/bb386106.aspx