I was having a hard time connecting my epic 4g to my kia and my computer as well. I know it sounds silly but someone might be encountering my same problem. I was using the usb cable for my droid which worked beautiful to charge the phone but wasn't sinking to my radio. As soon as i hooked it up to my computer the same it wouldn't give me the option to tether or anything. I tried the oem cable which i was only using to charge the phone and bingo it worked like a charm. Hopefully this would be help to anyone experiencing similar problems.