I have an on-going problem - two entirely different email accounts, then once in a while, this message kicks in - seen it on both accounts. Tnere is def nothing wrong with the account details or passwords, and this doesnt happen with PCs -only the ipads, and 2 separate ipads at that. Apple have a problem re they are way too arrogant to admit it and deal with it. I cannot find a solution, and Apple ave suggested nothing - check the internet, lots of this going about !