After upgrading to from VMWare Workstation 14 to 15, the shared folders are not available as mounts in linux guests, even when they show as enabled on the host. I even tried disabling them and re-enabling them, thinking it might need a refresh, to no avail. Virtual hardware on the linux guests has been upgraded to 15 as well.
Both guests are running Ubuntu 18.04.1 LTS with the latest open-vm-tools (last updated 9/27/2018).