Problem
I am unable to place VoIP calls on the handset or headset.
There is no dial tone.
Caller ID is not displayed.
Solution
PerSonoCall is not installed or not configured correctly (see “Installing the VoIP Utility software” on page 37).
Check that the correct system tray icon appears when you plug the USB cable into your computer’s USB port. If this icon does not appear, try plugging the USB cable into the port again. If this doesn’t work, close PerSonoCall and relaunch it by clicking the desktop icon. Relaunch Skype. If the problem still persists, remove the PerSonoCall software from your computer and reinstall it from the CD (see www.plantronics.com/downloads for more software troubleshooting tips).
The USB cable is disconnected or damaged. Unplug and replug the cable into both your handset and your computer.
You are using an older version of the VoIP service (Skype, etc.) on your computer that is not supported by your Calisto Pro Series. Download the latest version of your VoIP software.
Check the phone line connection from the base to the wall phone line jack to make sure they are properly connected.
If the headset doesn’t have a dial tone but the handset does, check to see if the headset is paired with
handset properly. Press the Headset 
button once and see if the headset icon is displayed on the handset screen. If the icon is not displayed, follow the steps in “Pairing with a new headset” on page941 to pair your headset with your handset.
Make sure you subscribe to caller ID service from your phone service provider.
The incoming call party has caller ID blocking and is restricting the displaying number.
Page 44
