The following error appears after running a discovery:
“Citrix MFCOM Service did not respond as expected. Ensure that your user account is a member of this computer's Distributed COM Users group if you are connecting to a remote server. Check the version of Citrix XenApp on the computer and make sure that a compatible version of Citrix MFCOM Service is installed and running.”

To resolve this issue, manage the legacy XenApp version 4.5 or XenApp version 5.0 for 2003 farm with the original console for that version. The XenApp 6.5 AppCenter Console cannot manage legacy servers. These versions should be managed as separate farm environments.
Note: XenApp version 4.5 or version 5.0 for 2003 uses MFCOM technology while XenApp version 6.5 uses PowerShell.

Problem Cause

This error might occur if you are attempting to manage XenApp version 4.5 or version 5.0 for 2003 servers with a XenApp 6.5 AppCenter Console.