Just double check that the software you are running on the networked computer is WideFS and not FSWide.  the latter is something that expands screen real estate to another computer.  WideFS is what allows communication through FSUIPC between networked computers.  Also for WideFS you need an additional purchased registration to the registered version of FSUIPC.

I'm an addict of remote FS app running on networked PC. I used to have Active Sky, IVAp + TeamSpeak (for IVAO). Unfortunately, with Prepar3D v4, I don't know how to make IVAp+TeamsSpeak running remotely.

I second previous comments. First, running away from the FS PC should be more profitable than the network bandwith and communication needed. (despite I didn't really benchmark). Second, be able to keep an eyes on the remote screen is still fun (private chat on IVAP) and this increase immersion on the main PC screen (only P3D displayed). 

Ah thanks Mark.  I was using them interchangeably 😳.  And maybe that is why I can't get widefs to install. Thought it was the same license as FSUIPC.