A TAPI service provider may request configuration information from hardware such as a PBX. Configuration information received from the hardware is stored in a list and compared to the existing configuration list. Two new lists are then generated: an added list and a deleted list. All devices in the deleted list are deleted from the internal database and deleted messages are sent to the TAPI service provider. All new devices are temporarily added to the internal database and addition messages are sent to the TAPI service provider. The new device configuration list is then saved, and the added devices are marked as permanent.