To allocate a new mailbox to an existing user which does not already have a mailbox:
Exchange Management Console Steps:
- Open the Exchange Management Console (EMC)
- Expand ‘Recipient Configuration’ and select ‘Mailbox’
- From the actions pane select ‘New Mailbox’
- Select ‘User mailbox’ then click the ‘Next’ button
- Select ‘Existing users’ and then click the ‘Add’ button
- Select the user then click ‘OK’
- Click on ‘Next’ , ‘Next’, then ‘New’
- The user account is now ‘mail enabled’ and has a mailbox.
Exchange Management Shell Command:
This task can also be done from the Exchange Management Shell command line.
Assuming the user is ‘bbuilder’ the command is:
Enable-Mailbox -Identity 'itsupportguides.com/CitySite/Users/Bob Builder' -Alias 'bbuilder'