I pickup upa use 7920 off ebay to add to my call manager test lab. I am having issues trying to do to a factory reset. I have tried to access the admin mode but it locks up the phone. I know you can buy the configuration utility cd but i would rather not have to put out that money. I need to know what are the most basic settings i have to use on a 1231 Ap to get the phone to register with call manager