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Topic: Connect to a second exchange mailbox in Outlook 2010 Adding a second mailbox in Outlook in an exchange environment can be useful for both the network admin or the user needed access to an old employee's messages. Steps: How to add a second mailbox in Outlook 2010 Click File from the file menu and hover over Info. Choose Account Settings and then Account Settings... again from the drop down menu.

Choose the exchange mailbox you'd like to add the mailbox to and select Change... directly above it.

Select More Settings... on the bottom right of the new window.

Select the Advanced tab on the top and select Add...

Enter the username of the user the mailbox belongs to in the Add Mailbox window.

Connecting to another user's mailbox in an exchange environment requires nothing more than adding the username. One prerequisite is permissions - the account you're logged in as will need full access permissions from the exchange server.