Can you open Control Panel > Programs & Features > Turn Windows features on or off and check that SMB01 is enabled.

Didn’t think SMB v1 was required to run Sonos unless you were using an NAS, and then it was required on the NAS and not the windows machine? 

I’m not, however, running Windows 11 yet to test this….

I am somewhat suspicious of Defender, and would recommend temporarily turning it off and testing to see if Sonos then works. If it continues to fail, then it isn’t Defender, and you can turn it back on. 
 

True!

Is the Sonos Windows Controller installed? That also installs the HTTP service for Sonos to access the music files. It should also configure the firewall correctly. 

Thanks but I’ve started the smb (automatic)

tried turning off defender and Sonos controller was installed with S2 configured as private network, Nothing works. I’m just going to drink instead of listening to music. Win 7 was so much easier before my machine died

Since so few of us have Windows 11 at this point, perhaps it might be best if you were to call Sonos Support directly to discuss it.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.

For what it’s worth, I’m pretty confident the issue isn’t Windows 11, but something else in your setup. 

Thanks everyone, I’ve sorted it out. removed sonos, rebooted, Went into the registry and deleted every reference to sonos. rebooted, reinstalled sonos, works fine now

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