Answer: Creating A Room mailbox in Exchange server is similar to the process we use to create a user mailbox.
Please remember that by default a Room mailbox user account is disabled in Active Directory after creating it.
To Create a Room Mailbox In Exchange Server 2010 Follow the steps below:
Right click on Mailbox icon under Recipient Configuration and select New Mailbox.
In the Wizard select Room Mailbox and click on Next.
Select New and click Next.
Fill in all the information.
Click on Finish when done.
To configure the Room Mailbox name, capacity, phone number, Policies and many other option just double click on the mailbox and configure the Room Mailbox.