Open the (usually garmin_kgen.exe or similar) from the extracted folder.

: Create a new text file using Notepad, paste the 25-character code inside, and save it as gmapsupp.unl . Place this file in the Garmin folder on your device's SD card. Alternative Method: gimgunlock

: Type your 10-digit Unit ID into the "Unit ID" field.

The tool will automatically remove the lock from the map file in seconds. Garmin Express™ | Update Maps and Devices