MS Exchange stores the email addresses for all users and other entities within the Active Directory.

It is very easy to add an email address to a User (Email Addresses tab on the properties page for an Exchange Enabled user) or to a public folder (Exchange System Manager > #Organisation# > Administrative Groups > #Administrative Group# > Folders > Public Folders : Select folder, right click > All Tasks > Mail Enable : Select Folder > Properties > Email Addresses) (O.K. easy when you know where to go).

Multiple email addresses can be added for a user or folder - but its very hard to see which email addresses have been assigned to which entity - especially as there are 2 different management consoles dependant on the type of entity, and secondary email addresses are not easily visible without opening the enity that contains them.

If you attempt to assign an email address which is already assigned to another entity, you get the following error message:

This email address aready exists in this organization.

ID no: XXXXXXX Exchange System Manager

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