Hi Matthias, >>> Sounds like the AP is broken and doesn't like some elements wpa_s >>> includes when nl80211 has certain capabilities ... > >> Just for reference, both my Windows 10 and my Android phone can connect >> to this 'Congstar'-labelled device without further configuration. I >> don't know what Windows and Android are doing behind the scenes though. > > If you have a means for capturing wireless sniffer traces of the frames > exchanged between the AP and these various station devices, it would be > useful to take a look at what the exact differences in the Association > Request frame contents. For the nl80211 interface case itself, it would > be interesting to see what is the exact information element that makes > the AP misbehave, e.g., by removing them one by one (this might be > either in wpa_supplicant or kernel) until the association succeeds. you can run iwmon (from iwd package) to capture the nl80211 traffic and it will decode the frames for you. You might want to also compare it to running iwd instead of wpa_supplicant since I have some vague memory we had this kind of issue and handled it somehow. Regards Marcel