I currently have an exchange server which is running SBS and Exchange. I am having trouble with certain domains getting rejected and others experiencing delay errors.
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<[url removed, login to view] #5.5.0 smtp;550 #5.1.0 Address rejected
Delivery to the following recipients has been delayed.
abcd(at)[url removed, login to view]
I have read this per KB Article Q300171
The mail servers of some Internet domains require that you create a valid PTR record that points the sending server's IP address to the local SMTP domain namespace. Sometimes these mail servers require that the PTR record match the actual FQDN of their SMTP Virtual Server on Exchange. Typically, this is the MX record. These Internet domains include [url removed, login to view], [url removed, login to view], Mindspring, Earthlink, and Hotmail. To send mail to these domains, create a valid PTR or a reverse lookup record on your company's external or Internet DNS server.
The added issue is that the Exchange Server is using the SMTP service of the ISP. SO I assume I have to set theses settings on the ISP.
If not I will need to be walked through configuring DNS correctly to resolve the errors.