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This is a good idea if you are using Switchvox apps like the Switchvox Softphone in Cellular mode, iPhone contacts in the Softphone app, Call Back features from a Digium Phone, etc. Also, it makes it easier for everyone if they can create External Contacts with just a 10-digit phone number.
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If a coworker is using Switchvox apps like the Switchvox Softphone in Cellular mode, or other tools that create calls with the Switchvox API, then you probably want to turn off any prepended digits for those users.
In each extension’s Advanced Profile Information:
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