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To call a person from your contacts list, simply click on the contact entry from the CONTACTS page; this will trigger the PROFILE within the CONTACTS page where you should use the call button in order to place the call (check case (1) from picture below). Following this, your extension will ring and only after you pick up the call, the remote party will be called.
To place calls outside your organization, you first need to check with your system administrator if you have the necessary calling permissions.
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