Ok, this feels like we’re getting somewhere. Let’s ignore the non-existent process shenanigans for now, and assume that it’s managing to open the named pipe correctly as shown in prc exp. This leaves us with only one conclusion - that the TCP channel is the one that is failing. As to why this could be the case, I’m still none the wiser.
I notice there are a few things on the netstat which although aren’t conflicting with the port assignment, could cause problems: fbserver (firebird SQL?) and OpenVPN. Could you try disabling these for the time-being? Also, what does your network connection setup look like on your PC? Do you have multiple network adapters, driver level virtualization, or anything disabled? I’m trying to think of anything that could cause the loopback connection to fail!