This subject has appeared before quite a while ago now, and a work around was found at the time to move all emails at once to the Trash bin. Well I read about a new (simpler!)way, in Business Insider today, and it works as follows........... While in Edit mode, select a single mail message such as the top one in the list, hold the move button at the bottom of the screen, and whilst continuing to hold the move button, unselect the email. After this, you will be asked if you want to move them all to the trash bin. Once they are all in the Trash bin you will be able to select them all and delete all of them. PLEASE NOTE: This does work on the iPad as well, but you won’t be asked to transfer your mails to Trash, it will go automatically, so be aware there’s NO going back if you do it on the iPad.