Your nuvi 65LMT's internal storage is no longer large enough to handle North America which has grown to a total of 4.11 GB without additional files.
Garmin Express would normally offer you to add an SD card ?.
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There is another way if Garmin Express didn't give that option, make a copy of your garmindevice.xml from your device and paste it to a folder called Garmin on a FAT 32 formatted SD card 16-32Gb. Without the device connected plug in the SD card to your PC (a clone of your device) and use Garmin Express to update it. Rearrange and rename the files as listed below. Insert SD card into nuvi 65
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