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To configure Global Caller ID:
Click on Options --> settings
Click the + sign next to Telecom Settings
The second option is Global Caller ID. Select one of the phone numbers you own from the list. If you have not yet added any phone numbers to your PBXtra , please read How do I add a phone number to my system?
Click Apply All Changes
To configure Caller ID on a per-extension basis:
Click on Extensions
Click any extension in the list that should have a unique Caller ID
From the Outbound Caller ID field select a phone number from the drop-down
Click "Apply All Changes"
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If you are using a VoIP connection you will need to verify that there is no fromuser specified in the advanced section for your VoIP account on the Options -> VoIPpage. The data in this field will always override any outgoing caller ID adjustments you page in your admin panel. If this setting is required by your VoIP carrier, you will not be able to adjust the Outbound Caller ID unless you contact your VoIP carrier.
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