Reading that back, it did not make much sense so will try again (and hit spell check)
I think I have resolved this but I am not sure which change made it work but I will list them:
The PC could see the HIB but I installed TWONKY and then I could then access it - i.e. see the sample pictures etc. To install TWONKY I right clicked on the WDTVHUB in my computer and clicked install. From memory I don’t believe that I could see the HUB from the PC when I first tried to install the HIB yesterday.
Powered off the hub (out of desperation).
Once the HUB was powered up I went to FILES and received the message ‘network share cannot be accessed’.
I then went to SETUP and changed the WORKGROUP to my PC HOMEGROUP name.
I went back to FILES and and selected NETWORK STORAGE and suddenly the media library is compiling.
Interesting (or not) when in the FILES menu I had previously selected MEDIA STORAGE which did see my PC but after selecting it, gave the error message I originally posted. However, when I made the above changes, the PC (name) was under NETWORK STORAGE (or similar).
I am not sure whether this helps anyone else or whether I have made just made so many changes that they just happened to solve problem.
Given that it has been 15 minutes with the COMPILING MEDIA LIBRARY message I have a feeling that it may be to no avail.