C7800 not recognizing hardwired CCTV

My C7800 will not recognize my CCTV system. We have turned the access controll on in the C7800 and this is the first time ever that the C7800 does not recognize that a new piece of equitment is attached to it.

I tried a new cable, reset the CCTV modem, reset the entire network and the C7800 still does not recognize the CCTV modem.

I did Block all new devices from connecting under the access controll. It should have ben listed as blocked in my list.

Any ideas be great!