The passwords like to Apple Mail, Gmail, and others – it is a ROYAL PAIN IN THE (Neck) to continue to to have to log out log into AppleID get an other APP password copy and past flip back to your client, paste and nice it checked the mail. One hour later… – (eM)Hey guess what you don’t look stressed enough yet – try this on for size, we forgot all of your passwords to all of your 6 e-mail account and did I mentioned something screwy is up with your SMTP settings – I know, I know your set them up the right way the first time and it worked and you were happy. Well that is were the rub seems to get sticky – HAPPY – ya no! so we did some shuffling and SMTP oh we need you to stop everything and pay more attention of us, over here and reinput all the information for I think 500th time, not to worry we will get it right at some point, hey if your that upset uninstall us…Mmmmmm that has crossed my mind 6 times already today. HELP
Have you considered that the problem might be with the AppleID?
Maybe contact them and ask.
A lot of this authentication issue sounds like the work of antivirus interference. Do you have AVG, Avast, or Kapersky installed? Are you using a VPN?