Exchange undeliverable messages – Server is not accepting connection

Hi all,

I emailed to external parties (Gmail) from my company mail server. After two days, I received bounce back saying “userA@gamil.com on 6/7/2008 7:45 PM
Could not deliver the message in the time limit specified. Please retry or contact your administrator.”

While running smtpdiag, the result shows “Error: Expected “220”. Server is not accepting connection. Failed to submit mail to gmail-smtp-in.1.google.com”

what does it actually mean? is it detected as spam from their side? the emails are just plain text and no attachment. I don’t understand why it is so.

Any idea? Please advice. Thanks!

Regards,
Suzanne