Difference in software packages.

Upgrade the software. See procedure "Software update via Communicator (DC update companion)".

There are other communication errors, including LDM 1 communication errors.

Solve LDM 1 communication errors first.

There are several LDM 1–x communication errors

• Make sure that all LDM boards are properly seated in the LDM case.

• If problem persists, replace the LDM. See service procedure "Replacing a Laser Drive Module".