Audible password not accepted/Computer not Connected to Internet
So I've just installed iTunes onto a new Windows 10 machine. I tried version 12.6, but for reasons probably too boring to go into, it wasn't working for me, and I uninstalled and put 10.7 back.
Everything's working fine except my Audible books. When I try and import them I get asked for a password it brings up a 'Do you want to allow this to make changes' dialogue and on saying yes, it immediately tells me that my username or password is not accepted. I know my usename and password. What I'm putting in is right.
I notice on the Advanced menu that I have the option to De-authorise my Audible account, which seems a sensible thing to try, but I get the same thing. Right password, wrong response.
I notice however that there's a help option on the password dialogue, and when I try that I get told "iTunes Help is unavailable because your computer isn’t connected to the Internet." Except that it is, I can see it downloading a podcast as it tells me that it's not connected to the internet.
So I conclude that something's got iTunes into thinking that it's not even worth trying to test out the password. Does anyone have any idea how to make it think again?
FWIW, as far as I can remember, the Audible account was one of the things that worked right with 12.6, but I'm not going back there.