I use windows mail. I followed your instructions, but when I get to add new mailbox and click on it, there is no option to type in a name or save it...any other suggestions?
POP3 accounts can't create folders on the server, which is what you are doing when creating a new folder on the iPad. You can't create local folders in Mail on the iPad.
Both IMAP and Exchange should be able to do this.. He said he had Windows Mail, by which I figured he meant either hotmail, an enterprise account, or some other flavor of Exchange. But I could be wrong.
By the way, Mail will let you save emails from one account into another account's folders. So, even if you have a POP account you can still get a second account and store your email there; iCloud, Gmail, and Yahoo as well as Hotmail should all work.