I have a need to change mail names of existing accounts. It appears that it could be done. In fact, after making the change in preferences of a mail name the new mail name appears in the list of mail names. However not only that I can not login with the new mail name and password but, even after rebooting, I can login with the original mail name and password and access the original mailbox, even though that original mail name does not exist anymore in the list. Help would be appreciated.