I purchased a 3598 and downloaded Express but it was not found by the programme on either Mac or PC. The shop exchanged it for another unit. The new unit has exactly the same problem. I also tried to register it on a friend's PC but with no success. Garmin Express, plug-in and drivers loaded. The unit is getting power but is not shown as an external drive or device on Mac or PC. What else can I do?
You have posted in a forum for Garmin Connect. Unfortunately, there is no Garmin forum covering your device. If your issue is with Garmin Express, you might want to post in a Garmin Express forum (PC or Mac).