Been there and done that Stanley. It’s apparently not on their “to do” list.

We come to the community to see if others have come up with solutions.

TP-Link’s Deco app which works with my router.

Thanks. I couldn’t figure out where such a command existed in Sonos’ controller. Wasn’t sure if something had changed, and I missed it, always a possibility.

Maybe this will help.

I have had the issue with adding a network share and indexing - the indexing fails part way through with the no longer available error shown previously.  I use a Boost connected to the router and Sonosnet to 8 devices.

Turn off all devices and the boost.  Connect one of the speakers directly to the router.  Restart the system with just one speaker. Re index the share.

Turn everything back on.  In my case I revert to  the Boost as my hub.

Hope this might help somebody 

Sonos, any update on getting this fixed?

Well I spoke too soon.  My music server disappeared. Tried to add and indexing failed part way in and got the same old error message about no longer being available.

I tried my previous solution - a single Play One connected to the router.  It failed to index.  I broke down my music into sub folders - A-C, D-F etc and tried to add a share for each.  1/3 of them added, the others failed.  For those that failed I added album folders one by one until the indexing failed.  Then went  file by file.  I couldn't find any obvious reason .  I looked at the meta data but all the CDs were ripped using dB Power amp at a similar time,

Out of desperation I converted one of the albums that stopped the share indexing from FLAC to mp3 and guess what - the indexing ran…

So Ive spent the afternoon batch converting 15000 tracks from FLAC to mp3.  
 

I can now index everything except files for  artists that begin with R or V - no Idea why. 
 

The Diagnostics /error message is useless.

I seem to think this issue appeared a while back, with the older S2 App too, with no solution. Maybe it is a bug in the indexing with some USB shared libraries attached to some routers.

I would perhaps wait until the new library features are added to the new Sonos App, reportedly due some time this month and if things then still do not work for you, go onto reproduce the indexing issues, then immediately submit a Sonos system diagnostic report from within the Sonos App, note it’s reference and then contact/chat with Sonos Support via this LINK to discuss the matter in detail and see what the Staff can perhaps then suggest to resolve the matter, or of course, you could just go ahead and report this now.