Is the USB port on? Try it with some other device. Try a different port. What program are you using to try to use it with? I can't remember if DM can load themes itself. Might be worth a shot.
Is the theme available as an OTA download? If so the easiest way would be downloading it directly to the BB...
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Plug into another usb port. Don't use a hub. Is Desktop manager installed? Did you install the phone's OS on your computer? You need the os from your carrier and then you need to run it so the os is actually installed on your computer so Desktop Manager can read the stuff on your phone.
Since when has DM had to have your official carrier's OS to work properly? I'm not using the official OS and haven't had issues using DM... Just say "no" when it asks if you want to update your phone's software.
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