According to the UG, the domain name must end with at least two characters:

However, an email ending with a-a as the domain name is not valid, even though it is three characters long.

It seems the domain name is only valid when the there are at least 2 characters in a row that are not -.
aa-a and a-aa are both valid.


It seems unlikely a user would be messing around with the email domains like this, but it's probably a good thing to update the restrictions in case a client has some strange obscure email.
According to the UG, the domain name must end with at least two characters:
However, an email ending with
a-aas the domain name is not valid, even though it is three characters long.It seems the domain name is only valid when the there are at least 2 characters in a row that are not
-.aa-aanda-aaare both valid.It seems unlikely a user would be messing around with the email domains like this, but it's probably a good thing to update the restrictions in case a client has some strange obscure email.