Translator           Hi, Hope you're doing well. Were you able to resolve this issue? Regards, Bruno Marques

Hi Guys,Thank you all for your tips and replies. We have just found the route cause: it was a network related issue. For some reason, the traffic for the that specific voice VLAN was being blocked on the end customer firewall.Thank you all one more t...

Hi Nithin, Thank you for your reply. We don't have any firewall between CUCM and phones. It seems that only 7821 IP Phones are not able to get registered on CUCM. I asked the end customer to unplug the network cable from one 7821 ip phone and connect...

@Saima HarrisHi, Did you manage something to solve the issue? Were you able to register you 7821 SIP phones?Thank You! Regards,Bruno Marques