Currently Being ModeratedAug 20, 2013 2:17 AM (in response to CL1167)
Try rebuilding the AOL mailbox.
Open Mac Mail and select the AOL inbox on the left.
From the menu bar click Mailbox > Rebuild
When it's done, quit and relaunch the Mail app.
AOL may have a limitation for file sizes. Deleting and resetting up the account would probably not help.