Dear All ,

I hope that i can figure out what is cause this problem from your experience

The problem is that once i begin to configure SIP extension by select the extension from unused IP phone and go to command 15-05 ,the system begin give us vacant number when anybody try to make an internal call , once we reboot the IP phones they begin take a new extension it was be used on other IP phone ... i immediately upload the backup file to the system without any result ... i have to reprogramming the extension again and manually and it happened frequently with this customer

Is that related to memory of CPU ? or Network issue ?


Any idea



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