Using an IP Address instead of a machine name in the CCA Management Server URL causes the CCA to fail to communicate with Management Server.
When installing the CCA, the user is prompted to enter a URL the CCA will use to connect to the management server.
Entering an IP address such as:
will be accepted and the installation will complete successfully. The CCA service will start successfully but never connect to the Management Server.
Examining the EventLog will show an Application EventLog entry (Event 9750) being generated stating "The Communications Agent failed to contact the Management Server. Error 401".
This occurs because IIS does not recognize the given IP address as being a computer belonging to the Intranet Security group and prompts for authentication. Because the CCA is a service it cannot show the authentication prompt and fails to connect. This can be verified by attempting to navigate on the client machine to the manifest.aspx file via IE first with the computer name and then with the IP address.
into IE should show an xml file with 'OK'. This page will be loaded in the Local Intranet group.
will cause IE to prompt for authentication. Failure to provide authentication will result in a 401 error. Providing authentication will result in IE showing an xml file with 'OK'. This page will be loaded in the Internet Group.
When entering a URL into the CCA, use the machine name rather than the IP address. Alternatively correctly configure the security policy so that the given IP address is recognized as being part of the intranet group for the System account.