Right click on your mailbox in the left hand corner of your All Mail Folders window pane. Click Properties for Mailbox – your name.
Click the Folder Size box.
This will show the Total size including any sub-folders in your mailbox. Click Close and OK. By default Exchange users are allocated 100 megabytes of quota.
If you require assistance in auto-archiving or setting up personal file folders to manage your quota, please contact the Service Desk at 864-4595, e-mail: firstname.lastname@example.org