I've had my phone for almost 3 months now. I've used my USB cable to charge it, work with HTC Sync and access its files as a USB storage device through the "disk drive" option. Now when I plug in the phone, it charges but does nothing else. The icon at the top of the screen in the notifications bar doesn't appear saying it's connected to a computer in any way. The computer doesn't say I have something plugged in. And when I go to My Computer, the drive doesn't show up where it usually does, or at all, for that matter. I've tried turning my computer off and on. I've turned my phone off and on. I've removed the battery and put it back in after 10 seconds, also done the same with my SD card. All of these multiple times. I know my USB cable is working because my phone charges. When I have the phone disconnected from the USB cable, but the cable plugged into the computer, the computer says there's an unknown device plugged into the USB drive. However, when I plug the phone into the cable, the message goes away and nothing happens but the phone charging. I have no idea what happened or why it happened now after working for so long. Please help.