if flashing an htc magic and error 170 occurs what should i do?
Even though I don't own this phone, I'll give it a shot. First, if you were rooted in the past with an unlocked bootloader, you will need to lock it before running the RUU.
In any event, you may benefit from installing HTC Sync (for the Magic) to your PC. You don't even need to run the program but it comes packaged with the USB recognition drivers. So once it's installed, plug the phone into the PC, then reboot the machine. When it restarts, hopefully it'll recognize the phone as being plugged in and will auto-install the drivers.
Then with the phone being recognized, retry the RUU running it as administrator if necessary (Win7 in particular).
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