Can't Unlock Maps


I use my Nuvi 855, turn it off, and a day or two later switch it on. It states "Can't Unlock Maps" and "Maps Not Routable" or similar. Sure enough in Settings-->Map-->Map Info my North America Map, the same one I downloaded on the device from Garmin using my lifetime map subscription is not listed.

I switch the unit off and on a few times, same result.

Then I pull the battery to do a hard reset. This time the maps are there and the nuvi starts like nothing ever happened.

Why would the Nuvi do this and how did it magically remember how to unlock my map? It doesn't give me confident in the robustness of the Garmin device...

Soft reset.

Actually pulling the battery is a soft reset (or power reset) and not a hard reset. A hard reset would prompt you "Do you want to erase all user data." The soft reset basically just bypasses the sleep mode quick boot and does a full boot.

But I am not sure why the boot from sleep mode is causing your problem. You might try connecting it to your computer and run a disk check. In Windows, go to My Compter, right click on the Garmin drive and select Properties. Click on the Tools tab, then click on Check Now under Error checking. To start with, I would remove the check mark for "Fix errors" to make sure it doesn't change anything on your nuvi. It should tell you though if it finds any errors in the file structure.

If it does find errors, make sure you do a complete backup of your nuvi BEFORE you try to fix anything.

Alan - Android Auto, Nuvi 3597LMTHD, Oregon 550T, Nuvi 855, Nuvi 755T, Lowrance Endura Sierra

Garmin has some instructions

Garmin has some instructions on their web site to resolve this problem (too bad they didn't work for me). Here they are:
How do I correct the message "Can't Unlock Maps. Your unit will not function without maps" on my Garmin mass storage device?

If you are getting the message "Can't Unlock Maps. Your unit will not function without maps," on your Garmin mass storage device, there may be an issue with the unlock file on your device.

Please follow the steps below to restore the mapping unlock file:

Log into your myGarmin account1
Select myMaps
Below the appropriate device, select the "Details" link
Look for the Unlock Code listed on this page
Copy all the unlock codes for your device
Close your internet browser
Right-Click on your Desktop
Click New and then click Text Document
Double-Click on the newly created Text Document icon from the desktop
Paste or type your unlock codes into the document
Click File and then click Save As
Change the file name to: gmapprom.unl
Change the "Save as type" to "All Files"
Click Save
Close the document (You should see the file gmapprom.unl on your Desktop)
Right-Click on the gmapprom.unl file and then click Copy
Connect your Garmin device to your computer and open Computer/My Computer
Right-Click on the 'nuvi (drive letter:)'2
Click Open
Right-Click on the Garmin folder and click Paste (See Step 21 for instructions specifically if your device is not one of the following: Quest series, StreetPilot series, nuvi 200 series, nuvi 205 series, nuvi 295W, nuvi 300 series, nuvi 465, nuvi 500 series, nuvi 600 series, nuvi 700 series, nuvi 800 series, zumo series 400, zumo 500, zumo 550 and zumo 660)
If your device is not one of the devices listed above, the gmapprom.unl file is required to be placed in the ".System" folder, which is a hidden system folder. In order for you to see the hidden ".System" folder:
For Windows XP:
In MyComputer go to the Tools menu and choose Folder Options...
Select the View tab
Select the radio button next to "Show hidden files and folders"
Uncheck the box next to "Hide protected operating system files (Recommended)"
Click OK
For Windows Vista & Windows 7:
In the Computer window go to the Organize menu and choose "Folder and search options"
Select the View tab
Select the radio button next to "Show hidden files, folders, or drives"
Uncheck the box next to "Hide protected operating system files (Recommended)"
Click Ok

Safely disconnect your Garmin device from the computer to complete the process. If you are having any issues duplicating the steps above or are still receiving the message "Can't unlock maps, your unit will not function without maps," please contact product support here:

1 The device must be registered to view the Unlock Code. To register your device, follow the steps outlined in the following article:{3a1f22c0-3ed8-11dd-d7af-000000000000}

2 In My Computer, some units may be labeled 'garmin (drive letter:).'

good the problem is solved

I would not have guessed that removing the battery, then putting it back in would have fixed the problem. But, it is good that it did.

I would have suggested logging into your garmin account and redownloading/reinstall the map.



Since your problem is solved, I wouldn't do anything.

If it aint broke....

Good to know

Thanks for the question. Good info to know should it ever happen to me.