Same problem here since Friday. Cannot send e-mails, neither from a mail software (Thunderbird/AppleMail) or directly through webmail. Also not receiving any mails from any source.
Seems mail server at x10hosting is facing trouble. Any schedule for fixing?
In fact, I can see that all SMTP ports (25, 465 or 587) are closed.
Also, I tried to e-mail from Yahoo to "any-mail-account"@"mydomain-at-x10hosting", and the mail server at Yahoo gives up trying to deliver those e-mails after a while.