MCU firmware is not genuine

If your device displays “MCU firmware is not genuine” during the firmware update, follow the steps below to fix this issue: 

  1. Press both buttons simultaneously so you see Identifier...
  2. Press both buttons again so you see The device will run in unsafe mode.
  3. Press both buttons one final time. You may be able to access the Dashboard. If you cannot, proceed to the repair tool instructions below.
  4. If you can see apps installed on the dashboard, please make sure to uninstall ALL of them. Don't worry, uninstalling the apps does not affect your crypto assets. You can easily reinstall them later.
  5. Proceed to the start of the firmware update in the Manager to try again.

Use the repair tool if it still displays MCU firmware is not genuine

If you cannot access the dashboard by pressing both buttons three times:

  1. Open the device repair tool by going into the Manager and waiting for the blue Repair button, or open it directly from: Settings > Help > Repair your Ledger device.

  2. Connect your Ledger Nano S.
  3. In Ledger Live, select MCU firmware is not genuine and click Repair. The repair process will start. If the Ledger Nano S is still displaying MCU firmware is not genuine, press both buttons three times, the device will then display the Dashboard and the update can continue. 
  4. If the loader is at 100% and the device stays stuck on Bootloader:
    Windows/Linux: Restart Ledger Live by pressing CTRL + R. Then start the repair tool once more.
    MacOS: Restart Ledger Live by pressing ⌘ + R. Then start the repair tool once more.

Still not solved?

If your problem is still not solved, there is probably a connection issue:

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