If you have tools enabled in your original course you must enable these same tools in the destination course or the items contained in that tool will not copy. One example of this is Attendance. If you have enabled Attendance in the original course but not the destination course the Attendance Registers will fail to copy and you will see an error message when you view the Copy Course Components History.
If you must enable a tool in the destination course click Course Admin in your course navbar and choose Tools from the list of options. See Enabling and disabling tools in LEARN for additional information.