Hi Felix,
Yes, the ZoneFlex R500 is supported on ZD 9.9.1.0.31 release, if you have enough
AP licenses, and it can communicate with your ZD. Look on your Dashboard tab, and
under Licensed APs for the maximum your ZD can manage, then under Devices Overview
where it shows your current # of APs. Are you within limits?
Next, from your message above, go to the Configure tab, Access Points page, and in
the third box down, Access Point Policies, there is a checkbox to "Automatically approve"
all join requests from APs. This sounds like it might be important, based on your message
above. In the top Access Points section on this page, do you see an option to click/approve
a pending AP? Good luck and best regards.