I get “Cannot Unlock Maps” or “Cannot Authenticate Maps” message, help!

I get “Cannot Unlock Maps” or “Cannot Authenticate Maps” message, help!

These error messages are from official Garmin licensed map, not ours, as our (talkytoaster) maps are not locked and not unicode format.

As Garmin state:

“If a Garmin device displays the message Can’t Unlock Maps or Can’t Authenticate Maps, it has detected a (Garmin supplied) map that cannot be validated for use with that device.”

If you have copied the Garmin supplied maps from a Garmin supplied map card to another (larger) MicroSD card and tried to use that in the Garmin device in place of the original Garmin supplied MicroSD map card, you may see this message during bootup of the Garmin device. The locked maps will not work or display.

Trying to copy or move any Garmin supplied maps will usually cause those maps to no longer function (on the new MicroSD card), hence the locked message, as the Garmin supplied maps are locked to the original MicroSD card, including the OS maps that Garmin offer.

The maps that Garmin supply are usually locked to a device (if installed to the internal storage) or to a MicroSD card they were first installed on; they cannot usually be moved as they are protected by copyright mechanisms that Garmin employ.

If you have a Fenix that supports maps, you may see an error “Cannot Authenticate Maps” after updating the Garmin TopoActive maps via Garmin Express, see here for more details on the issue, and possible solutions:

https://support.garmin.com/en-US/?faq=OdClLgKzPb4RrWMSucEnV8&productID=641479&searchQuery=Cannot%20Authenticate&tab=topics

Furthermore, if you have downloaded a Unicode version of a map from another site, please be aware that Garmin blocked the use of unicode maps back in 2016 on most of their existing models, and all new models, in an attempt to stop unauthorised use of their “official” maps (i.e. piracy).

The problem is that  this also has a knock-on affect on legitimate (third party) Unicode maps that are created from free data and using free and open source software.  Non-unicode maps such as the ones offered here, by Talkytoaster, work fine on supported Garmin devices, even where Unicode maps are blocked by firmware.

If you see messages like “Unlock map” or “Impossible to identify map” on device boot when you have copied a Unicode version of a map to your Garmin device, then your GPS doesn’t support unicode maps because of the Garmin firmware Unicode support block that Garmin imposed back in 2016.

All our Talkytoaster maps are not Unicode (non-unicode/latinised local language and/or English), so they are not affected by this change, and therefore work fine even on Garmin devices released after 2016, of those released before then that have had this block implemented (retrofitted) in a firmware update.

There is one scenario where you may get the "Cannot Unlock Maps" error message with our maps on specific Garmin models (such as the Edge 1000) and tihs only occurs where you have TWO copies of the same map (e.g. TT50-British-Isles) on the device or card at the same time; which you should not have as both maps will have the same internal map ID (regardless of the filename or date they were created). In this case simply remove the duplicate map.

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