Reset the IP Phone There are two methods that you can use in order to reset the Cisco IP phone: a factory reset, and a hard factory reset.
the image. Step 3. Continue to hold the MIC button and power on the phone (plug in the Ethernet cable or the power brick). When the lights that are located on the left, right, and back sides of the phone change from green to red, release the MIC button, as shown in the image.
Step 4. Press and hold the MIC button for approximately five seconds, and then release it. The lights should blink red twice. Step 5. Press and hold the MIC button. After approximately five seconds, the lights should begin to blink red continuously, which confirms the factory reset of the phone. Click this video in order to view the procedure:...