We have had success utilizing software distribution and image deployment using SCCM. We have been running SCCM SP2 R2 on a mix of Win2008 and Win2008 R2 servers for a couple of years now. We only utilize the multicasting feature occasionally and recently discovered that it is broken. These log entries have been logging for a couple of months now about once an hour: "SMS_MULTICAST_SERVICE_POINT,7101,MCS Control Manager detected MCS is not responding to HTTP requests. The http status code and text is 2147500037, ." The error message goes on to list three possible cause: 1. "Possible cause: Internet Information Services (IIS) isn't configured to listen on the ports over which SMS is configured to communicate. Solution: Verify that the designated Web Site is configured to use the same ports which SMS is configured to use." This wouldn't have changed, but what ports, where? 2. "Possible cause: The designated Web Site is disabled in IIS. Solution: Verify that the designated Web Site is enabled, and functioning properly." The multicast server has only the default site configured and I have verified that it is enabled. Functioning Properly, well that I'm not sure how to verify. 3. "Possible cause: The SMS ISAPI Application Identity does not have the requisite logon privileges. Solution: Verify that the account that the SMS ISAPI is configured to run under has not been denied batch logon rights through group policy. For more information, refer to Microsoft Knowledge Base." I'm not sure what the SMS ISAPI Application Identity is. I don't recall every setting this up. Where do I look for this and what should the permissions be? I've tried uninstalling and reinstalling both the MSP (turned off multicast for the DP) and WDS. Any other suggestions? Thanks, Steve