I spent about 10 hours trying to connect my 2nd Dlink DCS-5030L web camera. My 1st camera which I install 2 days before trying to add the 2nd camera took 10 minutes. This is what I think caused the problem, Dlink cameras only work on the 2.4 Mbps and the T3200M Modem kept trying to use the 5 Mbps band. After about 2 hours on the phone with the Dlink Technician he had me copy the configuration file from the working camera to the problem camera and after another attempt at connecting the camera using the WSP buttons it connected and has been working for 16 hours. I think there should be a way of forcing the modem to use the right band. Maybe there is but it's not very intuitive as both bands have the same name. It seems like the modem manufacturer made a smarter modem but not all connecting devices have kept up with the new technology.
The T3200M has a feature called Band Steering. It basically will switch from 5GHz to 2.4GHz and back depending on device and which one offers better signal strength to it. I'd recommend disabling that feature in the wireless settings on the modem. That will give you two separate networks. One 2.4GHz and one 5GHz.
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