You can search our knowledge base and look for "How to enable TKIP" for the full article, but you can enable TKIP or as Bill's pointed out use WEP instead, WAP-TKIP is just a bit more secure but either one will disable 11n functionality such as channel bonding or Block-Ack.
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If legacy clients are unable to connect to WLAN with WebUI encryption WPA-Mixed/Auto, a ZD CLI WLAN configuration command can be used to set WPA/TKIP.
SSH login to the ZoneDirector using a tool such as "Putty" and execute the following set of commands across the ZoneDirector to configure the TKIP based algorithm for the wlan.
ruckus>enable
ruckus#config
ruckus(config)#wlan
Eg:- ruckus(config)#wlan "BG-TKIP"
ruckus(config-wlan)#open wpa passphrase algorithm TKIP
Eg:- ruckus(config-wlan)#open wpa passphrase test1234 algorithm TKIP
ruckus(config-wlan)# exit
ruckus(config)#exit
Once after executing the above command, the WebUI interface will prevent configuring the wlan encryption options. However, still further changes can be made from the command line interface.
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