I've already got all the Micorsoft downloads mentioned above installed, but to be safe I'll delete & re-install them.
I'll give MultiPoolMiner V2.5.2 a go and see what happens; it may be a couple of days before I can do this - my Windows 10 PC just blew up as I was writing this so it will need fixing.
Thanks,
CMB.
Oh dear, I hope it's not too serious. If you get it up and running again feel free to post any issues on GitHub.