[roisto]

DD-WRT: v3.0-r59468 std (02/02/25)
Hardware: TP-Link ARCHER-C7 v5

External radius configured to 5 GHz Wireless interface's virtual interface. Radio mode is AP.

Windows 11 shows "This Wi-Fi network uses an older security standard that's being phased out" on connection.

It is propably because of "netsh wlan show all" shows no authentication and WEP encryption:
--8<--
SSID 1 : eetteri
Network type : Infrastructure
Authentication : Open
Encryption : WEP
BSSID 1 : c2:56:27:be:2a:cc
Signal : 8%
Radio type : 802.11a
Band : 5 GHz
Channel : 52
Basic rates (Mbps) : 6 12 24
Other rates (Mbps) : 9 18 36 48 54
--8<--

Windows refuses to connect this network so noting in radius' or dd-wrt's log.

Any advices?

BR,
-Risto

[roisto]

DD-WRT v3.0-r40559 std (08/06/19)
Hardware: Linksys EA6900

I configured the exactly the same config to this router and now enryption is None.:
--8<--
SSID 2 : eetteri
Network type : Infrastructure
Authentication : Open
Encryption : None
BSSID 1 : 1c:3b:f3:50:27:b5
Signal : 61%
Radio type : 802.11ac
Band : 5 GHz
Channel : 136
Basic rates (Mbps) : 6 12 24
Other rates (Mbps) : 9 18 36 48 54
--8<--

Obviously Windows would not let connect to this network either.

[kernel-panic69]

Is the wireless security mode set to WPA, Network Authentication to WPA2-Personal and CCMP-128 (AES)? Looks as if you are using older Wireless Security settings and therefore Windows 11 complains.

[roisto]

Such settings can not be chosen when external radius is configured. Please see the image of wireless security settings of this AP.

[kernel-panic69]

And the internal / external RADIUS server settings are? Also, you need to be on the current release.

EDIT: Found some light reading...

Windows 11 unable connect to WiFi with RADIUS

Windows 11 Cannot Connect to Wifi

Windows 11 cannot authentication with 802.1x radius authentication server.

Windows 11 forgets RADIUS WIFI Credentials

NPS server, Radius Auth and Wifi not auto connecting

Windows 11 22H2 not connecting to WPA Enterprise