Hello & Welcome,
Sorry I didn't see your question earlier and to hear of any issue you are having with your device.
To help you with this issue, may I ask:
1) What is the AGE of the device?
2) Have you EVER attempted to update the device in the past?
3) Does the device still work well - with the current maps?
4) Does the computer "see" the device - when connected to the computer?
I see it has been a few days and I just wanted to follow up to see if you have any more questions concerning this issue or if the issue was resolved?
I only ask because you may not be aware of the program that needs to be installed ON THE COMPUTER to update most Nuvi devices. That program is called Garmin Express and you can get it at the following link. There is even a short video on that page that will help get you started.
Click Here --> http://www.garmin.com/express
I look forward to any further questions or results that you may have.
Thanks, ***** *****--. .-(im)