During the Nano S update, when upgrading it to 1.4 version, this message may be displayed:
"MCU firmware is not genuine"
Do not worry, as this will not affect the security of your secrets, this issue is simply due to an update processed in reverse order.
When you see this message, you need to have your Recovery sheet with your 24 words on hand, as the process may reset your device.
Open the Ledger Manager application on your computer, and follow this guide:
Press both buttons on the Nano S several times to make the following screens scroll:
- "Identifier 0000...0000 "
- "The device will run in unsafe mode"
- "The configuration of your Nano S will be erased but apps will remain accessible"
- "To return to safe mode, connect the device to your computer, enter your PIN code and open the Ledger Manager app"
- "Unplug the device now to abort"
Be carefull, if you disconnect your Nano S at this step, the process above will be aborted, and will start over. If you want to continue updating your Nano S, keep pressing both buttons.
Wait until the Ledger Manager application synchronizes data. This step can take up to 10 minutes.
Click on "Firmwares"
and click on the "Install" green button
Then your Nano S will ask you to allow the Ledger Manager to update the firmware of your Nano S with version 1.4.1.
Press the right button above the check mark to confirm and allow the update to proceed.
The Nano S will now display "Update"
Press both buttons and the installation will start processing. This step can last several minutes.
After a while, your Nano S will display a "Welcome" message: your device is now updated.
Last step before using it: install the applications you need from the Ledger Manager!