Hi, have you encountered like "the number you dialed is not yet in service" when making an outside call from a SLT or PT. My PABX is KX-TES824 and I already installed 5 units of the same model in our 5 sister companies and this is the first time I encounter this kind of problem. It can receive an incoming call from CO and also I can make a call when I tap a SLT using an alligator clip directly to the CO. Anybody have any insight on this? TIA