How do I set up adb over usb with MyTouch 4g

I want to set up adb to work over usb with my MyTouch 4g. unfortunately, I am a total newb as far as android dev goes, so I really don't know what to ask. I have installed the sdk and the google usb driver but adb devices returns no devices. 开发者_开发问答usb debugging is turned on on my phone. My ultimate goal is to downgrade from Gingerbread back to Froyo so I can root.

Thanks

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My problem was solved by Darwind in the comments:

The Google USB drivers doesn't always work - get the HTC Sync which has USB drivers as well and install the full package. This should hopefully fix your problem - of course this is only for Windows