Abstract: An electronic lock is provided with an emergency technique by which the lock may be possibly opened in the event that the electronic memory used to store the authorized combinations for operation in unlocking of the lock becomes corrupted, damaged or is unable to provide a valid read of storage locations containing combinations. Upon the determination that an invalid read has occurred and that the invalid read has been verified for at least a plurality of additional read cycles, the lock is conditioned to accept an otherwise inoperable master combination for purposes of opening the lock. Under the prescribed conditions, the master combination is capable of opening the lock and providing access to the interior of the container carrying the lock, thus permitting either replacement or repair of the lock and also simultaneously eliminating the need for drilling or other destructive access to the interior of the container.