I recently added an AOL email account to 2011 Outlook for Mac.  I have a similar Earthlink email account which also has been set up in Outlook.  When emails are transferred from AOL to Outlook they are not removed from the AOL server.  Emails are removed from the Earthlink server when transferred to Outlook.  In Outlook Preferences, Accounts, Advanced the box is unchecked for "Leave a copy of message on server" for both accounts.  Why are emails removed from the Earthlink server and not from the AOL server?