When I connect my DX to a computer with the USB cable, I usually use "PC Mode" or "Windows Media Sync" instead of "USB Mass Storage". Because (a) then I can still access the SD card on the phone, and (b) I don't need to remember to unmount the SD card from the PC before disconnecting the cable. The strange thing is that on my work computer, I can copy files from the phone to the computer no problem. But on my home computer, when I try to copy a file, nothing happens. (I have Windows XP on both computers). I see the SD card directory tree in Explorer on the PC. I drag a file from one of the SC card folders into a folder on my PC. But then nothing happens. If I use "USB Mass Storage", then it works well okay. Any ideas why?