A day of my life I won't get back...

I spent the day being the IT consultant - too many frustrating hours. The only good thing was that at the end of the day, I think I had managed to sort out the problem.
For those interested, and I hope it won't be many, I think the MAC address authentication has been turned on so that only specific bits of kit could access the network. Not quite sure why and a frustration that a factory reset did not change the setting back to normal.
Happy days.