I've thought about trying this myself. I've never been a Garmin user before and didn't have any custom POI's to try yet. If you have files for them already, I would try putting them on a thumb drive and putting it in the USB port. Alternatively, you could burn them to a CD and try loading it through the CD/DVD drive. Possible one or the other of those locations would recognize the file format and upload it.Ok, I didn't see it anywhere else. Has anyone figured out how to upload personal POIs and routes into the 2012 Garmin GPS in the 300C's? I have been a Garmin user for 10 years so I have tons on my mobile unit I want to upload!!!