Add Search-Mailbox Role permissions

To use the Search-Mailbox command let you have to assign permissions to your account first.
In Exchange 2010 none of the preloaded role groups have the Mailbox Import Export role, The person performing the import or export must have the appropriate permissions within Exchange. The easiest way to grant this permission is by adding  Mailbox Import Export role to a role group.

Exchange Server 2010 comes with Roll-based Administration; you will need to run the following commands first though:

To create the role group we need to run the following:

New-RoleGroup "Mailbox Import-Export Management" -Roles "Mailbox Import Export"

This will create a group called “"Mailbox Import-Export Management"”, every user added to this group will have the right to run the import/export cmdlets, adding a user can be done by running the following:

Add-RoleGroupMember "Mailbox Import-Export Management" -Member <user account>

Or:

New-ManagementRoleAssignment –Role “Mailbox Import Export” –User “<username>”

This command gives the user permission to import and export mailboxes. Another way of doing this is creating an Active Directory group and adding permissions to this group using the following command:

New-ManagementRoleAssignment –Role “Mailbox Import Export” –Group “<usergroup>”

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