My apologies. It is an IP 400, not 500. We are on currently running 4.12 firmware. Previous to the upgrade, we were running 3.0 (i think. I know it was 3. something). We upgraded the configuration because our call forwarding was not working un the old firmware. Call forwarding to an outside number works GREAT now, but we took 2 steps backwards. Thanks again for any additional insight you might have