I have an error message from one of our staff:
This message is a warning that an email you are trying to send has not yet been delivered. You do not have to do anything yet as the email is still queued for delivery.
An email you addressed to email address : -- firstname.lastname@example.org
has not yet been delivered. The problem appears to be : -- Communications error
Additional information follows : -- All hosts are unavailable
This condition occurred after 6 attempt(s) to deliver over a period of 1 hour(s).
You will receive a rejection notice after a maximum of 2 days if the email cannot be delivered. If you sent the email to multiple recipients you will receive one of these messages for each one which is still undelivered, otherwise they have been sent.
We are using Windows SBS 2008 and MS Exchange 2007.
What it's mean and what should I do. Please help me, fast response are needed. Thanks