Hi,
I read that article and while it did not provide the solution exactly it did illuminate how this part of Fusion works and I was able to make some more sense of it.
When the fault was occurring, I could open a Fusion Electronics design it was opening the locally cached copy but giving me an error message that the requested file could not be opened. This was confusing me because the file was where it was supposed to be and was in fact being opened and displayed. What was not happening was that the same file stored on the Fusion cloud was not opening and therefore I could not work on anything for fear that the schematic and PCB get out of sync. Its an absolute failure when the schematic and PCB get out of sync so working with the locally cached copies (which do not sync) is a disaster waiting to happen.
As a result of some work I was doing over the weekend I had managed to upset the Ethernet adapter. Some websites would work while others did not. My best guess is that while I resurrected the Ethernet adapter to the extent that the internet worked it would still not connect to Fusion Cloud servers.
With the clarification within the link I was able to establish that the difficulty I was facing was a communication issue and therefore elected to take it to a PC pro. Yet by the time I got there whatever fault was there had corrected itself, making me look like a plonker....yet again!. Either way Fusion Electronics is now working again, and all my archived designs are still available to me...Phew!!!
Craig