Can't Authenticate Maps or Can't Unlock Maps error on an Approach Device

If a Garmin Approach device displays the message Can’t Unlock Maps or Can't Authenticate Maps, it has detected a map that cannot be validated for use with that device.

This can be caused by:

• A problem with the data in the map file
• Incorrect or missing unlock information for an installed map

To resolve these issues:

• If the issue occurred as a result of updating the maps, ensure that Garmin Express is up to date and reinstall the maps. Instructions for reinstalling courses can be found under related content. Be sure to use the Safely Remove Hardware option on a Windows computer or the Eject Device option on a MAC after the update has completed. Even though the update appears to complete, the write-caching feature on some computers may have not have completely built or transferred the map to the device. Ejecting the device before disconnecting it can prevent this error.¹
• If maps have not been installed or updated recently, update the maps using Garmin Express.

The Garmin device should now power on without displaying the error message.

  ¹To safely remove the device:

 Windows: Press the Windows key +  E, Right-click the Garmin device and choose Eject (if the device is not listed it does not need to be ejected)

 Mac: Drag the device to the trash or select the Finder and choose the Eject symbol next to the Garmin device