Gerry?
Your hangover must have subsided by now?
There has been a development. I decided to see if this Native host/user defibed issue was anything to do with .net. So I repaired .net4 and downloaded .dotnet 4.5.
I now get messages in my action centre (should that be inaction centre?) that I have downloads waiting for me. I clicked on Windows update and after a while it reported a list of downloads, but nothing else. I then tried update again and got the same error message as before, 800B0100.
Maybe I should get on with suing Microsoft for breach of contract? Or even breach of promise as they told me I would be amazed at what Windows 7 and I can do together...........