Failure to Completely Index Music

Hello,

I'm a new Sonos user and have experienced some difficulties in indexing the library of music stored on my router. I have tried searching the forums, but have not turned up any solutions.

System summary:
Western Digital My Net N900C Router (with an internal 2TB HDD)
Sonos Bridge connected directly to router, 2xSonos Play:5 wireless
Controlled through Desktop PC and iOS (iPhone and iPad)
System was initially set up on a PC running Windows Vista

Issue:
Although Sonos appears to connect easily to the library on the Public share on the router, it has not successfully indexed the music on the router-based HDD. Two tries resulted in the "Indexing..." message running for several hours and then disappearing with no music indexed. On the third try, I saw similar behavior from the "Indexing..." message, but the first 10 artists (all starting with "A") were indexed and play now with no difficulty.

I have tried shutting down all devices (wired and wireless) that access my Wifi and then restarted in the following order: Router, Bridge, each Play:5, Modem, other devices... This has not resolved the problem. When I pull up my Network Matrix, all of the nodes are green.

Any advice would be greatly appreciated!

Thanks,
James