In the settings for the Playbar,  have you selected 'disable WiFi '? 

If so, then you have actually turned off the Playbar's wireless capability, disabling SonosNet and making it impossible for the Sub to connect.  Change this setting to 'Enable WiFi' but leave the Playbar wired.

(If this is the explanation then I blame Sonos for the highly misleading way in which this setting is labelled. )

Thank you very much John, super helpful.  Yes, it was my bad, as I disabled WiFi on the Playbar.  I enabled WiFi so now my Sub works.

The Playbar and Sub now show as WM: 0.  However, the other speakers (Play5, 2 Play1s) still show as WM: 1.  Is there something I need to do to get them on Sonosnet?  I unplugged one of the Play1 and connected it to the ethernet, but when I unplugged the ethernet it went back to showing as WM: 1.

Thanks again for your help.  And it would be helpful if Sonos labelled it with a parenthetical “Disable WiFi (disable Sonosnet)”.

Hi. Glad it helped. Usually a power cycle of the speakers will get them onto SonosNet but it doesn't always work. 

In Settings go to System, Network, Networks and remove your WiFi details.  Speakers will then have no option but to connect to SonosNet. 

Thanks again John.  When I go to System, Network, and Networks, It shows my wifi on the In Use screen.  But there is no way to remove it.  Perhaps the WiFi is In Use because of my Sonos Move?

Note, I also unplugged the Play5 and 2 Play1s to see if that would allow me to remove the WiFi network.  But that didn’t work either.

If you power off the Move can you remove the WiFi details?

Do you have 2.4GHz and 5GHz bands and do they have separate SSIDs?

Also, what happens if you tap the words "wireless setup?

You’re good.  I powered off the Move and then was able to remove the WiFi.  However, I’ve tried multiple times to connect my Play1 and Play5 - through factory reset and with an ethernet connection.  However, when I remove the ethernet, the speaker is disconnected.  When I try to connect the Play without an ethernet, I get a screen that says “Your Play has been added, but may not appear in the System tab.  If so, unplug the power cord and plug it back in to finish setup from the System tab.”  When I unplug the power cord and plug it back in, nothing happens.

I have a Google Nest router which doesn’t have separate 2.4 and 5GHz bands, so I only have one SSID.

So as of now, my Playbar (connected with ethernet) and Sub are connected to the system.  My WiFi is disabled, and my Play5 and 2-Play1s aren’t connecting.  My Move was connected before I powered it down.

I do appreciate your time and help.  Thanks.

Strange.…

So the Google Nest system has a router..... any mesh satellites? Any other access points, extenders etc?

How did this situation arise? Was this all working at some point?

Google Nest is a new router that i put in, so it’s a new setup.  There are 2 Google access points that create the mesh network.  Before I put in this Google router, the Sonos speakers were connected through Sonosnet (I believe).  Thanks.

Is there any other device involved such as an ISP router still acting as a modem?

The only reason I can think of for the speakers not connecting to SonosNet is that there is another WiFi network they are connecting to. Is that possible?

And one further thing you might try is to factory reset JUST ONE of the missing speakers then add it to your system using Add Product. 

A power cycle of your router and access points may also be worth a try.

Thank you again John.  I rebooted the Google Nest router and then reset the Playbar.  After doing both, I was able to connect all speakers through Sonosnet.  I haven’t turned my Move on yet, but I’m hopeful it will work.  I couldn’t have figured this out without you, thank you!

That’s great.  I’m very pleased to have helped.