Webmail/Popmail Problems Again!

Can’t login through webmail again. The "@domain.com" also disappeared.

I have also been trying to update my passwords with no luck since last night. I created a new mailbox and it got to webmail fine but access is being rejected via Apple’s Mail client (all the other addresses worked fine here).

Webmail login is by the friendly email address by Apple Mail login is often by the m######## mailbox name, so check the latter is correct.