IP Cortex VoIP PABX User Manual page 27

Switch between calls by pressing the line button of the caller you wish
to speak to. Each call can be disconnected independently by hanging
up the caller you are speaking to.
Transferring a Call
Unattended: Click "XFER", dial the destination number, and press
"XFER". You are no-longer part of the call.
Attended: Place the received call on hold by clicking the "HOLD"
button. Dial the destination number as normal. Speak with the callee
when answered. Click "XFER" and then click on the line button to join
this caller to.
Setting up an n-way Conference
Dial a call as normal, and place it on hold. Dial any further parties, or
receive additional calls as shown above. Once all parties are present,
click the "CONF" button to join everyone into a conference. The voice
quality of the conference will vary based on the power of your PC
CPU, and the number of parties joined.
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If the Eyebeam user disconnects the call, all parties are disconnected.
To break the conference without disconnecting, click "CONF"
Picking up Voicemail
If voicemail is waiting, an envelope symbol appears on the phone
display. Dial whatever short-code has been configured on your PABX
to pick-up voicemail.