First you have to go to Garmin and download their free program called WebUpdater.
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To download the latest unit
software visit Garmin website: www.garmin.com/webupdater
After installing WebUpdater once from the Garmin
website, perform all future software updates from your computer. Simply connect
your compatible Garmin device to your computer, then run WebUpdater from your
computer's "Start Menu" by selecting "Start",
"Programs", "Garmin", and finally "WebUpdater"
REMEMBER: It takes hours to do a complete a map update.
Unless you bought the Lifetime maps you may have to pay for current United States maps.