XFOR: Exchange Server NNTP Service Fails With 500 Command Not Recognized

The Internet News Service fails to receive a push feed from an authorized Internet news provider. When the newsfeed provider issues an IHAVE command to the Exchange Server computer, the following error message may occur:

The Internet News Service has failed to validate the newsfeed provider as an accepted server.

In addition to specifying the Remote USENET Site Name and Host Name, the IP address or fully qualified domain name of the newsfeed server needs to be added to the Additional Inbound Hosts (Remote host name) field. It is recommended that the IP address be used to avoid any name resolution problems.

When configured correctly, the "Newsfeed type" listed on the General tab of the Newsfeed will read either "Newsgroups are accepted inbound," or "Newsgroups are accepted inbound and pushed outbound." You cannot edit the newsfeed property after it has been configured. When you are running the Newsfeed Setup Wizard, be sure that the "Inbound newsfeed type" is set to "Accept incoming messages (typical)."

Microsoft has confirmed this to be a problem in Microsoft Exchange Server, version 5.5.