Go to SETTINGS
Then to APPLICATION MANAGER
Then scroll top menu across to the left until you get to ALL
Then scroll down to EMAIL and click on it
Then go to the STORAGE area and press CLEAR DATA
Exit out and return to EMAIL on home screen
Open EMAIL app, and it should be ready to set up again as you did initially when you bought the phone.
If you had a Gmail acct in your EMAIL app as well as your two AOL accounts, you will have to re-add it as "OTHER" so that you can toggle between the 3 accounts in your one EMAIL app.