Plex Media Player ver 2.1.1 does not see server

After upgrading to the 2.1.1 series of PMP, the server / PMS can no longer be found by PMP on clients but does work locally on the server / PMS with PMP. If I switch back to PMP versions 1.3.5 or 1.3.9, PMP sees the server / PMS as expected and videos , music, etc… can be played.
I have tried two versions of PMS:
1.9.2.4285-9f65b88ae
1.9.3.4290-9798172d4
Thanks