Can't get NG-100G-F2 40GigE module to link and the Tx and Rx leds are red, even though the Module's status led is green.

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Can't get NG-100G-F2 40GigE module to link and the Tx and Rx leds are red, even though the Module's status led is green.
Make sure you are using the supported VIAVI QSFP adaptor. It should be VIAVI branded and marked ACC-6065A.