Thanks for replying, I tried to install as admin but no luck. I have hunted high and low over the interweb and found the solution last night....
Solution as follows:-
In right hand pane if UpperFilters has a value, delete it. If LowerFilters has a value, delete it. Reboot.
In my case it only had a value for LowerFilters, but I deleted it, rebooted and the drive was back to normal.