2x Thin Client PXE Boot Issue - TCAC008

We use the 2x Thin Client from www.2x.com it is a really cool PXE booting Thin Client for Terminal Services and Citrix. It has been working at our clients for months without a hitch but his morning all our users had this message displayed on their computers when starting up.

We searched the 2x Knowledge Base and could not find this error and it is not in the manual either so we were a but stumped.

Then we got a call from another office that they had the same issue. The penny dropped it must be something used at each site, the licence!

We checked and the licence we had entered was lost in the back end server application, we re entered the details and we were back in business.