In the machine in which the data is encrypted, the following message appears after the controller board is replaced.
Using the encryption key kept by the customer, get an SD card ready for restoration, and then execute the restoration. (If the encryption key is already stored on an SD card, use that SD card.)
If the customer has lost the encryption key, get ready an SD card for canceling data encryption, and then execute forced start-up without an encryption key. (In this case, the existing data in the NVRAM and microSD card is deleted.)
The notes relating to the microSD card do not apply to the models not equipped with a microSD card.