Answer: Setting a storage limit and retention period on a mailbox databases on Exchange server 2010 is a simple task.
Remember that it’s recommended to place the users in separate databases based on their role, department or location which will make it easy to apply limits in the future.
To set storage limit and retention period on a mailbox database follow the steps below:
Open EMC – > Organization Configuration -> Mailbox – > Database Management -> Right click on the database you need to set the limit and select Properties.
Select the Limit tab, in this tab you can set all the limits you need, when finish click on Apply and OK.