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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03/04/2014

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:

  1. Log into your myGarmin account at http://my.garmin.com2
  2. Click on the myMaps tab
  3. Click on the Details link next to your device
  4. Locate the most current unlock code for your device underneath the Installed Maps heading
  5. Copy all the unlock codes for your device

Creating an Unlock Code File for PC:

  1. Connect your Garmin device to your computer with a data transfer USB cable
  2. Double-Click on My Computer or Computer located on the Desktop or in your Start Menu
  3. Right-Click on the Garmin drive
  4. Click Explore
  5. Double-Click on the Garmin folder3
  6. Right-Click in a blank space in this window
  7. Move your mouse over the word New, then Select Text Document
  8. Press Enter / Return on your keyboard
  9. Double-Click on the New Text Document. This will open the New Text Document in a window called Notepad
  10. 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
  11. Select File
  12. Select Save As
  13. Change the Save As Type to All Files
  14. Type gmapprom.unl in all lower-case letters for the File Name
  15. Select Save
  16. Close the Notepad window
  17. Delete the file named New Text Document
  18. 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:

  1. Connect your Garmin device to your computer with a data transfer USB cable
  2. Open the TextEdit application located in the Applications folder
  3. Click Format
  4. Select Make Plain Text
  5. 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
  6. Click Save As and name the file: gmapprom.unl
  7. Uncheck the box "If no extension is provided, use '.txt'
  8. Save the file to your Desktop
  9. Double-Click on the Garmin device icon that is mounted on the Desktop
  10. Double-Click on the Garmin folder3
  11. Copy the gmapprom.unl file from the Desktop to the Garmin folder on your device
  12. 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 nuvi 2405, 2407, 2408, 2505, 2507, 2508, 2707, 2708, 3400, 3500, 3507, 3508 series, zumo 350, zumo 390, dezl 760, or Camper/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:

  1. Click the Start button in Windows
  2. Select Help and Support
  3. In the Search box type "Hidden" without the quotes
  4. 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:

  1. Double-click on the GARMIN device icon on the desktop to open
  2. Click the "Go" menu option at the top of your screen in the menu bar
  3. Click "Go to folder..."
  4. Type ".system" (without the quotes and in lower case letters)
  5. Click OK

The .system folder will now be present in the folder list.

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