Some Lowrance Software versions do not work with popular .lcm mapping files. If your GPS doesn't read a mapping card, inserting a card slows the GPS, freezes it or constantly restarts it - check your software version. For compatibility with all mapping cards, we recommend the following versions of software:Globalmap: AnyTrophy: 1.0Elite 5m Baja: AnyElite 7 TI: 18.2 or 5.0Elite 5 TI: 18.2 or 5.0HDS Gen 2: 2.5HDS Gen 1: AnyHDS Gen 3: 18.2 or 7.0HDS Carbon: 18.2 or 4.0Elite 7 HD: 4.0After downloading the file, copy the unzipped files onto a blank SD card (not the card with the mapping). Power off the GPS, place the card into the GPS unit and turn the GPS on. Call us if you need additional help.