Hi, Maybe this can be helpful, found this at the mitel site.
Body/Solutions
When programming IP Networking Configuration on a CXi 3300 Controller please be aware of the following.
Under System IP Configuration / Quality of Service, if you change the VLAN ID and priority you will not be able to connect directly to the uplink port or layer 2 ports with your PC. When you change these settings you are putting the uplink and layer 2 ports into a different VLAN and therefore need a VLAN aware NIC in your PC or connect the uplink port to a trunk port on a VLAN aware layer 2 switch.
If you have changed this by mistake then use the following procedure to recover the CXi.
1) Connect a serial cable to the RS232 port. Open hyperterminal and connect with 9600,8,N,1.
2) Type vlan_off and press return.
3) After 30 seconds you will be able to connect to the RTC address through ESM via the uplink or layer 2 ports.
4) Change the VLAN ID to 1 and Priority to 0.
5) Reboot the CXi 3300 controller.
Regards U