using Garmin nuvi 250 usb port to charge only

Welcome to the site.

We usually recommend the following.

There is a "Learn" button in the upper right of this page next to "red light cameras" that takes you to a Getting Started page. It is worthwhile visiting this page.

To make navigation easy, most browsers provide the following option. When you want to follow a link - but still keep your current page open - you can hold down the "Ctrl" key as you left-click on a link. That action will open a new "Tab" in your browser up on the "Tab" bar. When you then left-click on that new "Tab", you will follow the link - leaving the "Tab" you are now reading open and available to click on and return here.

So, using the "Learn" link, you might try the "Ctrl" - left-click sequence and then return here. You can return by either "X-ing" out of the "Getting Started" page (using the "X" on the "Tab" itself) or just left-clicking on the "Tab" for the page you are on right now.

Note that the Learn Button will give you access to two valuable reference pages -
the "Index" to all of the FAQs (Frequently Asked Questions) and the Glossary of Terms and Links.

Since you are new here, I encourage you to go through a couple of the Tutorials.

The first link makes sure the settings on your computer are such that you can do more advanced POI loading.
http://www.poi-factory.com/node/30393

The next link helps you make a backup of your GPS by attaching it to your computer. (NEVER do anything to your GPS until you have a backup). It also assures that you put your (newer) unit into a state where you can see all of the folders there.
http://www.poi-factory.com/node/30394

Let us know how we can help you enjoy your GPS.

Yeah, the USB port is meant for connecting to a computer to download map updates, etc. from Garmin's website.

It's not meant for charging, but its good that you found a way.