Trying to set up a new Symfonisk to an existing network, and it won't finalize the connection. Any ideas or suggestions?

Thought I’d add my two cents to this and tell you what SOLVED the issue for me: changing WiFi router settings.

Short story: IKEA Symfonisk could be “added” to my Sonos system (already had a Move) using the Mobile App, but not recognized (so no functionality). Tried updating the Sonos system using the PC app as suggested by others, didn’t fix it. Contacted local Sonos support (they were very friendly and helpful)  - after trying all their tricks they suggested it could be an issue with my Wifi router.

So I called my internet and router provider, and turned our they had a list of recommended Wifi router settings to make Sonos work. They helped me ensure that the Wifi settings were as follows:

1. 2.4 GHz must be activated.

2. The SSID for 2.4GHz and 5GHz WiFi networks must be unique (ie. distinct IDs/names. If not previously enabled, it may be wise to keep the 2.4 Ghz name the same as the old name to make existing systems recognize it and label the 5Ghz channel as XXX_5G).

3. Client AP isolation should (likely) be OFF.

4. Use “b/g mode” for the 2.4 Ghz .

5. Use WPA2/AESK

6. WiFi channel should be in “LOCKED” mode.

7. Airtime fairness should be OFF

8. WPS should be OFF

9. Ipv6 setting STATEFUL. (as opposed to stateless)

10. Channel width: 20MHz.

(settings 2, 4, 6 and 10 were “incorrect” on my Wifi)

After changing setting and reconnecting to the Wifi (the 2.4 Ghz channel), initially the Symfonisk wasn’t recognized in the Mobile App. using the Sonos PC App now solved it: If I remember correctly, I unplugged and reconnected the IKEA Symfonisk, clicked the Reset Controller (Help menu) in the PC app, and then “connect to existing system”. The app asked me to update the system and I clicked OK. After that, it was possible to recognize the Symfonisk in the Mobile app (under System settings).

The Symfonisk and the Move speaker now work perfectly using the Mobile App (knock on wood)!