The ability to use a local library with Sonos was never “eliminated”, the documentation linked below has all the information you need to set one up. If you are having issues it might be worth reaching out to Sonos support.

https://support.sonos.com/en-au/article/add-your-music-library-to-sonos

Nope.  Doesn’t work.  And if it was never “eliminated” why did I receive multiple emails from Sonos apologizing for the delays in fixing things that were screwed up royally by the May app release???  

It wasn’t eliminated, but some protocols changed, which caused some issues that might require some tweaks on your end. Yes, it’s a pain, but if you post some details about your set-up and what error messages you’re receiving, you might be able to get some help from the community on what the problem might be. There are some pretty smart and helpful people here. Otherwise contacting Sonos support is your other option.

I use a MacBook Air.  I’ve tried adding my music library repeatedly since they “improved” the app in May as I have lots of music and playlists established there that I’ve always been able to use with Sonos.  I was told by Sonos support back in June that the functionality to do that had been removed with the May release but they would be working on restoring the capability.  I also got an email from Sonos in July also promising to restore it.  Beyond that….crickets from Sonos.

I’ve tried adding it by selecting clicking the + and selecting My Music folder...doesn’t work. I go thru the requested steps and get the following response:  “Unable to add the shared folder “//MacBook-Air/Music” to your music library (913).

Sharing for the folder is enabled in my Mac.  Sonos is enabled to run in the background.  I’ve also tried the “NAS” method.  That doesn’t work either (although I don’t understand why it ever would).

 Of the three choices on the Sonos computer controller the NAS choice is the only one that does work.  They should take away the other two to minimize confusion.

The path you are entering looks incorrect. It needs to be an SMB path as per the docs, eg “\\MacBook-Air\Music” - note the back slashes not forward slashes.

Follow these docs carfefully https://support.sonos.com/en-au/article/share-your-macos-music-folder-with-sonos

Since are using apple I would recommend iTunes Remote app on iOS as a far better way to search and control the library on your computer using AirPlay than Sonos integration will ever offer.

Or better still if you have an Apple Music subscription sync your library to the cloud and all your local playlists and songs will be available to stream directly through the Sonos Apple Music integration without the local library setup, and to stream and download on any other device like your iPhone. Apple Music sync includes iTunes Match so you get free download + streaming of lossless versions of any local songs that match to what is available on Apple Music, and it doesn’t mess with local metadata. It’s amazing, trust me.

 Mine are all forward slashes.

I’ve been using the PC controller to access my NAS library continuously through all of the updates. There have been a few hiccups requiring me to redefine the shares, but these were minor. There is an annoyance with respect to displaying Contributing Artists. This is being worked out.

I finally gave up on trying to get it to work by using the Sonos app on my laptop.  I thought I’d give it a try using the Sonos app on my phone.  Lo and behold, it worked using the “my music” option.  Don’t ask me why, but after taking forever to update, my music library and playlists are all available again.  Thanks for all of the advice...I’m bookmarking everything for the future, just in case!