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There are a few different ways of manipulating the caller id that is sent to a given gateway; each of these apply to any call sent out through that gateway. Normally, any of these settings may be overridden by settings that are specific to a particular user as described below; to prevent a user-specified value from overriding the gateway value, check the 'Ignore user Caller ID' checkbox.
Setting a single Caller ID for all outbound calls
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If you have some users whose extensions cannot be transformed by a pattern to the Caller ID value you want for them, you can set a specific value on the User Caller ID screen; as with the gateway, you can check the 'Block Caller ID' to make all calls made by the user anonymous:
Unless the gateway configuration has set the 'Ignore user Caller ID' flag, a user specific value takes precedence over the value set by a gateway.
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Caller ID can also be defined at the User Group level. If set in the group and not overridden by the specific user, all users in the group share the same caller ID number for outgoing calls.
As with any group setting, if a user is in several groups, the setting of the last group is the one that controls the active caller id.
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