Yep, had to change all the ip addresses to clients (school) requirements, then just connected back into server rack for Host pc to detect as normal via configuration utility.
As I say, I've got to sort the McAfee problem, but I was pulling my hair out, uninstalled/reinstalled net2 software, tried different ip range, etc etc, by chance I disabled av and firewall and found the firewall problem, not a happy bunny, took me the best part of half a day to fathom out what was causing the problem.