Correcting the Message "Can't Unlock Maps" or "Can't Authenticate Maps" on a Garmin Automotive Device

Can’t Unlock Maps or Can't Authenticate Maps displays when the device detects a map that cannot be validated for use with that device.

This can be caused by:

• Installing a memory card that contains maps intended for a different device

• Copying maps from one device to another

• A problem or corruption with the data in the map file

• Incorrect or missing unlock information for an installed map

To resolve these issues:

• If a memory card is inserted into the device, remove the card and restart the device. If the error message no longer displays, there is a locked map on the memory card.

  • If the memory card was previously used in another device, there are most likely maps installed to the card that is only unlocked to the previous device. The maps will either need to be deleted or reinstalled for the current device to unlock them.

  • Maps may have been installed on the memory card with MapInstall or MapSource that were not unlocked for the device. See Unlock the maps for the device on the computer and then reinstall them to the memory card.

  • If the memory card was preloaded with the map, contact Product Support.

  • If the memory card contains maps that were copied from another preloaded card, delete the map files from the card and use the original card. Preloaded maps cannot be copied from one card to another.

If the above situations do not apply or the issue is not resolved, proceed to the following steps. 

• If the issue occurred as a result of updating the maps, ensure that Garmin Express is up to date and reinstall the maps.

• If the device is being updated on a Windows computer, be sure to use the Safely Remove Hardware option (if available) after the update has completed. Even though the update appears to complete, the write-caching feature on some computers may have not completely built or transferred the map to the device. Ejecting the device before disconnecting it can prevent this error.

To safely remove the device from a Windows PC:

1. Press the Windows key +  E

2. Click This PC (Windows 10 only)

3. Right-click the Garmin device

4, Click Eject (If there is no Eject option, the device does not need to be ejected)

• If this message is displayed after installing a Downloadable Content (DLC) map, reinstall the map and try again. If the issue persists, follow the steps in this FAQ.

• If maps have not been installed or updated recently, update the maps using Garmin Express if an update is available.

• Maps may have been installed to the device with MapInstall or MapSource that were not unlocked for the device. Unlock the maps for the device on the computer and then reinstall them to the device.

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