Same issue here.

Using my @outlook.com account during registration throwed that error

I had to open a gmail.com account to register; then same error when trying to update the mail address...

Someone else reported this error one month ago, they told they'll look into it but it is still unresolved.

Yeah we have an issue with a TON of bot using outlook. If we allow it we will end up with 1M+ spam account. We are waiting for them to calm down a bit before re-authorizing this domain.

Same here with @Yahoo @t-online.de and @magenta.de adresses so I used my spam overcrowded @web.de. i would love to change it to an email adress wich I don’t want to het rid of. Cant you just put one of these Elements into it, where we have to prove we are human by kclicking pictures and stuff?

Have a similar issue with trying to update the mail address... got the error message 'The domain of your email is not authorized.'
Funny thing is that the questionable domain is my own private domain also used for the registration some time ago, hence it is known to the admins. Wondering about the restrictive behavior... seems little bit too far fetched.