_

When a Caller ID does not show on the called party phone, there can be several places to prevent or Block outbound caller ID:

1) The Web Portal:  In the PBX of the customer, you have a menu option for "Outbound CLI Mapping" which can be set to the default "Anonymous" or attached to a DID that has been ordered to the company. If Anonymous, it is similar to CALLER ID Block.

2) The system (*) Star code of *67 was performed from the phone, which activates the Block Caller ID. The *68 will unblock caller ID.

3) On the Grandstream phone, you can perform a BLOCK CALLER ID by picking up the handset, then dialing *30 or *67 which will then indicate on the phone display the caller ID is Block for all subsequent calls with *30 and for just the next call if *67. This is happening at the phone level.  The *31 or *82 will unblock the caller id on the phone.

You may have to perform some detective work by checking if it is only the one phone, or every phone and then work your way back from the above scenarios. If all fails to alleviate the issue, please contact support via our help desk.