Hi @mplsmw 

Welcome to the Sonos Community!

There are a myriad of possible reasons as to why your Music Library indexing attempts are failing. I recommend you get in touch with our technical support team who have tools at their disposal that will allow them to give you advice specific to your Sonos system and what it reports.

It may help, however, to reboot every device involved - your speakers, your phone, your computer (if that’s where the music is stored) and your router.

Please do not reset any Sonos devices - it is very unlikely to help.

I hope this helps. 

I have had this issue in the past.  In my case I solved it by adding a new destination for my music library and deleting the old path in Sonos.  Then did a library refresh.  After that had complete I changed the Music library path back to where all my music was.

Just DON’T delete the Library itself, just the path in Sonos.