The problem described here is back again after restarting my macbook pro upon arriving home from work.
I repeated the steps as suggested in the other thread, but those did not fix the problem this time. The local Plex app does seem to connect to the PMS on my macbook pro as indicated on the upper right hand corner of the Plex app when it starts, but my libraries do not show up. Again, all other Plex apps on ios, samsung tv, and the dlna server work with out problems.
Attached is the Plex Media Server.log file.
Hope someone can help.