Why does redhat-upgrade-tool cannot load any configuration from preupgrade-assistant section ?

Issue

• Most of the preupgrade assistant rule fails with errors

  # preupg -vd
  Result table with checks and their results for 'main contents':
  -------------------------------------------------------------------------------------------------------------------
  |BIND9 configuration compatibility                                                             |notapplicable     |
  |Dnsmasq                                                                                       |notapplicable     |
  |Samba SELinux context check                                                                   |notapplicable     |
  |FreeRADIUS                                                                                    |notapplicable     |
  |Identity Management Server                                                                    |notapplicable     |
  |Tomcat configuration compatibility check                                                      |notapplicable     |
  |Obsoleting Hardware Abstraction Layer                                                         |notapplicable     |
  |java-1.8.0-ibm compatibility check                                                            |notapplicable     |
  |Read-only FHS directories                                                                     |pass              |
  |CGROUP_DAEMON in sysconfig scripts                                                            |pass              |
  |VCS repositories                                                                              |informational     |
  |Removable media in the /etc/fstab file                                                        |informational     |
  |The yum configuration file                                                                    |informational     |
  |Ethernet interface naming                                                                     |needs_inspection  |
  |Repositories for Kickstart                                                                    |needs_inspection  |
  |Configuration files to be reviewed                                                            |error             |
  |File lists for the manual migration                                                           |error             |
  |Bacula Backup Software                                                                        |error             |
  |MySQL configuration                                                                           |error             |
  |MySQL data stack                                                                              |error             |
  |Changes related to moving from MySQL to MariaDB                                               |error             |
  |PostgreSQL                                                                                    |error             |
  |GNOME desktop environment                                                                     |error             |
  |KDE desktop environment                                                                       |error             |
  |POWER6 processors                                                                             |error             |
  |Graphic drivers not supported in Red Hat Enterprise Linux 7                                   |error             |
  |Input drivers not supported in Red Hat Enterprise Linux 7                                     |error             |
  |Kernel networking drivers not available in Red Hat Enterprise Linux 7                         |error             |
  |Kernel storage drivers not available in Red Hat Enterprise Linux 7                            |error             |
  |Red Hat Directory Server                                                                      |error             |
     :
  

• Verifying results.html file generated by preupg report the below error

  preupg.log.ERROR: Can't load any configuration from section preupgrade-assistant!