No, this should not be the cause. If the machine is set to active, was previously successfully scanned and the software is currently listed in the machine's Software tab, the machine should be listed in the report. Is this a Windows 10 computer by any chance? If so, we haven't added support for the latest Windows 10 release yet, which can cause issues in a number of reports and widgets. See
this forum thread for more information and a manual fix.