^a Error Types 1, 16, 22, 50, 52, 65, 66, 69, 88 are typically associated with administration problems and are not expected to be temporary. The administered connection is not retried and the failure is alarmed immediately. The alarm threshold specified by the customer is ignored.

^b Error Types 1, 28: The address of the destination endpoint is: an unassigned number (1), has an invalid number format (28) , or is restricted from terminating calls due to Class of Restriction (Access Denied). Verify that the destination address is correct and that the destination endpoint is administered. The destination endpoint is not administered on the switch where this error is logged.

^c Error Type 2: A request has been made to use a transit network or common carrier that cannot be accessed. Check the routing pattern used by this administered connection and verify that the inter-exchange carrier specified is correct.

^d Error Types 6, 21, 31, 127: The exact failure cause is unknown or has been mapped to one of these values. If this is a permanent condition, try reversing the direction of the Administered Connection (originate the administered connection from the destination switch). This may yield another failure cause.

^e Error Type 17: The destination endpoint is not available. Check the status of the destination endpoint at the far-end switch. The status for the destination endpoint will not be available on the switch where this error is logged. At the far end, use status access-endpoint or status data-module to see whether the endpoint is busy, out-of-service, or otherwise unavailable.

^f Error Types 18, 102: this switch sent an ISDN message to another switch that either did not respond (18) or did not respond within the time allowed (102) . This could be due to link failure, or congestion, or an outage at the other switch.

^g Error Type 22: the address of the destination endpoint has changed. Change the administered connection accordingly. The destination endpoint will not be administered on the switch where this error is logged.

^h Error Types 34, 42, 44, 58: a resource (for example, a circuit or bearer capability) required by the administered connection is not currently available.

ⁱ Error Types 38, 41: a network failure (38) or temporary failure (41) has occurred. Error Log entries for other MOs (for example, DS1-BD) may indicate a local problem.