Follow along with the video below to see how to install our site as a web app on your home screen.
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Menu>settings>applications>usb settings... here you will see some more usb settings like samsung kies, media player, mass storage, ask on connection
Link is 'dead' -just the hompage for the 4G and there are no available downloads showing for this phone from the Samsung site (even the owners manual). WTF?!

I just got my EPIC yesterday and tried to load pictures onto my computer, when I encountered this issue. The computer wouldn't recognize the EPIC as a USB device. I use windows 7 64, so I tried the 3g tether, downloaded drivers from samsung, uninstalled, reinstalled..nothing would work. Then, I happened to just see some comments that people said to try different USB ports. I tried the 2 on the front of my computer with no luck. I thought the suggestion to use the back USB ports was kind of silly, but nothing was working so why not try it. I climbed under the desk, plugged it in and guess what...IT WORKED. Now there are no issues with my computer recognizing the EPIC. So, I would reccommend using the USB ports straight off the board.
Tried just about everything. The only thing that worked, in the end, was just patiently plugging and unplugging the usb cable.. again and again, until it recognized it as something usable.
+1, do not plug your droid into an auxilary port on the front of your PC use the ports in the back, works like a charm. This needs to be a sticky!!!!

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Connect your phone to your computer via USB. Give it a few seconds.
Next, PULL DOWN your notification bar.
Next, tap your finger on "USB CONNECTED"
- is this an OS version issue?I don't know about cables or using specific USB ports on your PC, but my problem ended up being USB Debugging. I turned off USB Debugging and the phone connected right away, and Windows recognized it exactly correctly, and I saw the three options on the screen they say you should see.
I posted the details here if anyone is interested:
http://androidforums.com/epic-4g-tips-tricks/193272-how-successfully-mount-epic-4g.html#post1732103
Hope this helps people!