ERROR: Failed sending email to

[athena]

1.5.5f Linux
Sorry to trouble anyone over what must be a very simple issue but...

Are there settings in Configuragion > Email options or any place else in the admin that would keep a perfectly sound working email address from working as our Account mail box?

I have tried a variety of email addresses with a variety of options selected and only one, with the same url as the store, that is no longer an active email works.

The email we want to use to send from is not on the same server so I do not have "Emails must send from known domain? -No". I've tried it with "Yes" and there is no difference. Only the one old email will work.

Just keep seeing this when we run a test to send: ERROR: Failed sending email to:....

The host and server port work fine when retrieving mail with Outlook. Any insights appreciated. I've exhausted talking to our tech support on our Linux server over this. They can't see any issues on their end.

[athena]

php option rather than smtpauth seems to be working even though the email is on a windows server and requires smtpauth, shop on linux, sorry i'm such an idiot about all this.