I actually have some experience in getting .NET to talk to COBOL flat file databases and I agree it's not something that anyone seems to have managed to get 100

I actually have some experience in getting .NET to talk to COBOL flat file databases and I agree it's not something that anyone seems to have managed to get 100% right. CONNX is a pretty good product but still seems to suffer from locking and needing to manually restart the service from time to time, and this was on a project much smaller in scale than anything a group as big as Dixons would need. As a .NET developer myself I certainly don't envy the guys who had to deal with all our complaints from the shop floor, and of course the ageing SCO system had to be replaced with something. These days it would probably be something lightweight and browser based as opposed to a full-blown WinForms application, pretty much emulating the old terminal-based setup (hardware-wise if not interface-wise). The keyboard navigation and super-low-latency feedback of the old system would still be a huge challenge, though.