Many thanks for your reply. My IOS is 9.3.5. I have gone through the Setting up & repairing email to assure the settings were as required, but this did not allow me to connect. The email message I received indicated that I had five addresses (I thought I had only one!) and all were acceptable. Up to 30 October everything worked perfectly well, which caused me to think that something must have happened around an update. My username "dwain" and password work perfectly well on my desktop computer running Windows 10. I discovered today, however, that the account with that username has apparently been invalidated.