I had a few days of panic when my DAW (Logic) would always hang when starting up a session with VEP7 instantiations connecting to my slave machine. When the hanging occurred, the VEP7 on the slave would pop up an instance but wouldn't complete the loading as if the DAW wasn't able to fully "send" instructions. When I quit VEP7 on the slave, the Logic session would continue to load - which was a huge relief. Also, I was able to create sessions and connect with VEP7 (slave) but upon reconnecting later on, the hanging would occur again. I should also add - connecting to VEP7 locally was totally fine.
So after much head scratching, reformatting my slave (because I did the HIgh Sierra upgrade fiasco with an older MP), reading numerous forums, and finally stumbling on this thread I figured out my problem! With the discussion of possible network issues I thought it'd be good to look into my own network settings.
THE PROBLEM: NORTON 360 Content Filter - DISABLE THIS!
I had installed Norton 360 and it automatically puts this content filter feature into the network settings. I disabled it and then voila everything connected as expected.
Hope this helps!
W