Earlier this afternoon I was having the same problem that has been described before--iphone could not log into icloud mail while on cellular network (worked fine on wifi). Later, several emails I sent from my macbook disappeared without ever showing up in sent mail box using apple mail app; I got a response to one of them so I know it went through. Finally and worstly, two important folders in my icloud email account disappeared this evening. Not able to locate them on mail app on macbook, imac, or iphone, or using web icloud interface on the two computers.
Is icloud mail going completely screwy this evening? The rest is annoying but the random loss of folders is enough to have me considering switching email providers.
Has anyone had folders randomly disappear before and then show back up?