Need help with Lantastic real old version

Is anyone familiar with lantastic? I have a client who owns a video store with 2 old 486 computers peer to peer network using bnc cable. One computer is the "server" and the other a dumb terminal that is directed to the "server" They run a program that was custom made for them, and the guy that originally set them up years ago is MIA. The problem they are having is that the dumb terminal keeps going off the network. It will be sitting there and all of a sudden a message pops up saying cannot find drive d (which is the server) But only every so often (mostly when they are real busy and need the other system - as murphys law would have it.)I replaced the dumb terminal because the cmos was bad and couldnt be replaced and cloned the drive...this was a couple weeks ago. It was up and running for 2-3 wks no problems. I have tested the cable, even re-routed it to avoid any pinches etc. But then the other day it went out again and they said that the main frame had locked up and the printer wouldnt work...
turning off the dummy and rebooting the main one solved it temporarily, but my poor client was on vacation and got a billion phone calls from her employees when all this was happening. I feel really bad because nothing seems to work. what i want to do is change the cabling...but that would involve installing 2 new network cards, and the drivers and I'm kinda weary doing that without knowing how it will effect the lantastic program. any suggestions would be great
thanx :)

It sounds like an old Arc net installation - what you will need to be careful of is that you have the correct drivers for whatever version of Lantastic your client is using for the new ethernet cards.

Arcnet was a fine technology in it's day - cheap and fast it provided a solution for environments where ethernet would be cost prohibitive - however Arcnet has long term faults - the cable connectors wear out and need to be replaced, and the cards go bad.

I would replace the cards with 10bt cards and a crossover cable - just set them up in two other workstations and install lantastic to make sure the new NIC's bind to the lantastic client and you can see the shares and transfer files.