All of a sudden there are certain sending domain unable to send mail to my company. They get a returned error message as follows.
"Unable to deliver message to user@******.com
Delivery Failed for the following reason:
Error Delivering message to "my IP address"
"This has been a temporary failure. We will attempt to deliver this message every hour............."
Very generic message. How can I find some type of log that tells me what is happening and why? There is absolutely nothing in the Windows Event log. SBS2008 running Exchange 2007. Thanks