But when I go to my maps on the device the screen is empty. I have logged into my Garmin and it says I have MPC Map and City Navigator Europe NTU 2013.10, UK & Ireland – Map only, Apr 12. But now my satnav says “cannot unlock maps” when it starts up. Hi I have a Garmin nuvi 2310, i have updated my software using Garmin Express. Change to the directory in which you downloaded the files, (i.e., c: garmin), and run the executable file (.exe). Download the MapInstall update file into a directory on your hard drive. Fixed an issue where MapInstall was writing maps to the wrong location on memory cards. Garmin UnLocker Alternative v8.0.1 - () 1. GPS Forums - Tomtom, iGO, Garmin, Sygic, Navigon, Cars GPS.