Try removing and re-adding your music library.

If problems persist, tell us exactly where your music library is stored (NAS, USB, PC, Mac etc). Also which BT router (though historically speaking every BT router is janky in some way).

I had the same issue with an external SSD connected to the USB port of router and set to USB share on the Network. I was able to add the music library off the SSD in Sonos but doing updates to the music library didn’t work and got the same message you did.

So, I purchased a SanDisk Cruzer Fit thumb drive. Loaded it with my music again. Plugged it into the router USB port and now everything is working normally. Sonos can access the flash drive and can update the music library.

Well I spoke too soon above. I added a new MP3 to that shared, network USB flash drive. Did an “Update Music Library” and now Sonos doesn’t detected the shared drive anymore.

Makes no sense. 

Does your router require a mount and unmount operation for the USB drive port?

No. Never had to unmount it. The USB has been attached to the router since I got it.

Which router? Maybe someone else has an idea.

Every time I see a nas/router/pc music library post I’m loving my Raspberry Pi SMB server more and more. :-)

The router is a TP-Link Deco BE63 mesh router.

Not much here: https://www.tp-link.com/us/support/faq/3341/

Maybe try rebooting the router once you reinsert the USB drive?

I’ve read that page several times and my USB flash drive is setup and attached. I don’t remove it. It’s Mapped as a Network Drive in Windows and when I add new music (drag and drop) to it, I like to tell Sonos to Update The Music Library. This is it where Sonos fails and says the network path doesn’t exist, when it does.

The router is set to reboot weekly in the wee hours of the morning. It does not make sense to reboot the router after EACH time I drop new music into that network connected thumb drive.

That really does sound like a shortcoming in the NAS software, have you tried turning the Network Neighborhood setting off and back on to see if that will force things back to normal operation?

Worst case get it working and submit a diagnostic, break it and submit another, Contact Sonos support as they will be able to see internal data not available to us users.

I haven’t tried the Network Neighborhood setting off and back on. Sounds like a good idea to do that in the router, but that’s not ideal to do that each time I added new music to that USB network share.

Glitches like this are why I built my own, simple, fully under my control, NAS device.

The cost of a Raspberry Pi Zero , a SD card and power brick quickly paid me back with lack of frustration and glitching.

Just looked, my Pi has been running, ignored and untouched for 117 days. Not that it was touched then, that was when we lost utility power for a few minutes and I shut everything down to save the UPS batteries.

So I turned off the Network Neighborhood off and than back on. Nothing. Also, did a new Scan of the USB drive on the router’s app. Nothing. Sonos still can’t index the USB shared drive whenever I add new music to it.

I have to remove the Music Library location in Sonos and then re-add it. It’s the only way it will work at Indexing the drive again. Meanwhile my music files are MP3 with minimally tagged info and have been evaluated by Mp3val for errors.

This is a Sonos issue and not an issue with our routers, as I see this is an ongoing issue for 1-2 years that hasn’t been addressed.

You can always force the error, submit a diagnostic and ask Sonos Support (call them) to look at the hidden internal data and see if they can identify an issue.

SMB has been an issue since day one with Sonos, sometimes it is Sonos sometimes it is the other device and sometimes it is that the spec isn’t well written and devices that meet it still can’t connect.

Laying all the blame on Sonos disregards the thousands of SMB users that have no issues.

Yeah. When people complain about an issue, thousands of others do not have the same issue. It doesn’t meant the issue doesn’t exist.

We all have different systems and networks. If we provide feedback of the issues to Sonos, perhaps there would be a solution or fix. But from what I’ve read of countless threads of this very same issue, a solution hasn’t been provide in the past 2 years.

I’ve made it known with Sonos Tech Support with a submitted diagnostic, two different times. They don’t have a fix and when on the phone, they act like they’ve never heard of this issue before. I know that they have. It’s all over this community.

The “fix” is to remove the Music Library pointing to that Share in the app, and then re-add it. Sucks.

That is not a fix, that is a work-around for the underlying problem.

Since Sonos locked us out of most internal data “for our own safety” fixing things going wrong is more challenging than it needs to be.

If Sonos support is no help I’d look for other options that do work. My Raspberry Pi based SMB server or SMB gateway both work flawlessly. Other options exist too, even the less technical one here.
 

Live Journal: Stan

You knew what I meant about fix. I don’t regard it a fix at all but it’s the only workaround that allows me to index the music library from that USB share. A most tedious one.

Not interested in Raspberry Pi, nor an always-on NAS drive. I’m only interested in getting this USB port share to work with Sonos. It works with Windows 11 as well as my Roku Ultra. It not fully with Sonos.

Then about all you can do is raise the issue with Sonos Support and the support department of your router. Not much we users here in the community forums can do for you.

It doesn’t seem like a priority to tech support, when it was addressed.

Probably not since most NAS options work with Sonos developers spending time and money on a few edge cases isn’t going to pay off for them.

You’d have better luck with your router’s manufacturer, maybe they can tell you where the SMB settings are, what they are and how to edit them. If you can do that the odds of working with Sonos go way up. Lots of SMB settings posts here to look at and try once you are into the router’s config.

If you (or anyone else) get frustrated enough a $15 Pi Zero 2 W is a good option for this. If you don’t have the additional bits needed the kit options are nice too. Just add the Open Media Vault software and you are good.

 https://www.canakit.com/raspberry-pi-zero-2-w.html?cid=usd&src=raspberrypi

Open Media Vault link: https://stan-miller.livejournal.com/940.html

I just wrote to TP-Link:

I am having issues with my Sonos system (v16.1, the latest) doing an Index of my music on my USB Share attached to my main Deco BE63 Mesh. Sonos keeps telling me the USB flash shared drive can't be read to update the Index of the files. I have communicated with Sonos several times and they are unsure what's going on. Media Share is On. Network Neighborhood is On. Deco BE63 sees my USB flash drive. Windows 11 Pro sees my USB flash drive too, in the Network.

What are the SMB settings? Is it SMB v1, v2 or v3? How do we edit them, if possible?

Hopefully you’ll hear something back.

If you have settings questions you can search here to see what has worked for others.

So I did some tweaking to my USB share. Instead of pointing to the Music folder of this drive, I point to it’s IP address and subsequent “g” folder, in the Sonos app’s Music Library.

After I add new music to this USB share, I have to go into the router’s TP-Link Deco app and than to the USB Sharing setting and hit “Scan for USB Devices”. Give it a couple of minutes, and only then can I do an “Update Music Library Now” to re-index in the Sonos app. These multiple steps work

Also, TP-Link stated this about the Deco 63 Router I am using via email support:
For the SAMBA, Deco BE63 supports V1 and V2. Deco will automatically negotiate with the front-end device. If front-end device uses V1, and Deco also uses V1. This is a built-in mechanism of Deco and cannot be changed, so there are no related setting options.