01:07 ACARS deliberately switched off?
If the Airplane took off at 1241am, maybe at 107am the PNF needed to relay a departure message to company and used the Center radio taking it out of VHF DATA? Maybe he never put it back to VHF DATA, the EICAS would show VHF DATA message of course but no ACARS. Not sure what comms set up MH have. Can someone verify? Is HF DATA installed on COMM 1 or 2. They may not have been set either. Is SATCOM installed? What DMI's/MEL's did the airplane carry? Just saying, there are other ways ACARS could be turned off inadvertently.