I’ve Given up trying to login on my AppleTV 4K box.
Looking at the internet this error seems at least 3years old and still now have not resolved it - good luck on taking on Netflix and Prime - i’ve Already cancelled my free 1 month trial
if get password wrong then I get a password wrong error - that’s fine and to be expected.
However if I use the correct password (that works on a nowtv stick and on Apple ipad and Apple phone) I get the dreaded 1610 fail to login error message.
I’ve tried deleting app (several times) including then unplugging appletv box then restarting appletv box then reinstalling app. but I don’t think it’s clearing all the data as it still remembers several email accounts and the kids pass on the wife’s account (who also can’t log on).
before anyone suggests it I am not prepared to do a factory reset - Netflix, synched Apple Music and prime are all working perfectly.