3CX is working on the problem. For me there is a workaround. Maybe it also works for you.cviviani said:i have the same problem on sbs with 2 nic.
i have open the ports on ras section to the wan nic.
with the 3cx voipphone i can register and make calls .
but with 3cx pbx it will not register i get also a failure with firewall test on port 4200.
do you find a solution ?
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