Not used it for a while, turned it on... message came up 'Cannot unlock maps'
So plugged it in to the mac, checked for updates, message says mapping up to date.
Unplugged it again, booted up .. message again 'cannot unlock maps'
Me and garmin don't seem miscible
Will this help? You can create your own file
How do I correct the message "Can't Unlock Maps. Your unit will not function without maps" on my Garmin mass storage device?
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10/08/2013
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 file1:
Retrieving Your Unlock Codes:
Log into your myGarmin account at
http://my.garmin.com2
Click on the myMaps tab
Click on the Details link next to your device
Locate the most current unlock code for your device underneath the Installed Maps heading
Copy all the unlock codes for your device
Creating an Unlock Code File for PC:
Connect your Garmin device to your computer with a data transfer USB cable
Double-Click on My Computer or Computer located on the Desktop or in your Start Menu
Right-Click on the Garmin drive
Click Explore
Double-Click on the Garmin folder3
Right-Click in a blank space in this window
Move your mouse over the word New, then Select Text Document
Press Enter / Return on your keyboard
Double-Click on the New Text Document. This will open the New Text Document in a window called Notepad
Type or paste the unlock code that is listed in the Manage Maps section of your myGarmin account in all capital letters with no spaces or symbols
Select File
Select Save As
Change the Save As Type to All Files
Type gmapprom.unl in all lower-case letters for the File Name
Select Save
Close the Notepad window
Delete the file named New Text Document
Disconnect the GPS device from your computer
The unlock file is successfully created and transferred to the device.
Creating an Unlock Code File for Mac:
Connect your Garmin device to your computer with a data transfer USB cable
Open the TextEdit application located in the Applications folder
Click Format
Select Make Plain Text
Type or paste in the unlock codes that you retrieved from your myGarmin account. The unlock code should be in all capital letters with no spaces or symbols
Click Save As and name the file: gmapprom.unl
Uncheck the box "If no extension is provided, use '.txt'
Save the file to your Desktop
Double-Click on the Garmin device icon that is mounted on the Desktop
Double-Click on the Garmin folder3
Copy the gmapprom.unl file from the Desktop to the Garmin folder on your device
Eject the Garmin drive
The unlock file is successfully created and transferred to the device.
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:
https://buy.garmin.com/support/searchSupport/escalateForm.faces
1If you have a Camper 760, nuvi 2405, 2407, 2408, 2505, 2507, 2508, 2707, 2708, 3400, 3500, 3507, 3508 series, zumo 350, zumo 390, dezl 760, or RV 760 devices, contact Product Support instead of proceeding with these steps:
http://www.garmin.com/us/support/contact
2The device must be registered to view the Unlock Code. To register your device, follow the steps outlined in the following article: https://buy.garmin.com/support/searchSupport/case.faces?caseId={3a1f22c0-3ed8-11dd-d7af-000000000000}
3If your device is a nuvi 30, 40, 50, 1100, 1200, 1300, 1400, 1690, 2200, 2300, 2400, 3700 series, LIVE 1695, LIVE 2300 series, zumo 220, 665 or dezl 560 device, then the gmapprom.unl file is required to be placed in the ".System" folder instead of the Garmin folder. The ".System" folder is a hidden folder in the Garmin drive. To access the hidden ".System" folder, please follow the steps below:
On Windows:
Click the Start button in Windows
Select Help and Support
In the Search box type "Hidden" without the quotes
Select the result with instructions on displaying or showing hidden files or folders
You should now see instructions on how to view hidden files and folder
On a Mac:
Double-click on the GARMIN device icon on the desktop to open
Click the "Go" menu option at the top of your screen in the menu bar
Click "Go to folder..."
Type ".system" (without the quotes and in lower case letters)
Click OK
The .system folder will now be present in the folder list.
