Correct me if I'm wrong, but I believe the SB-600 has no commander mode. To work commander from the d7000 you have to use the pop-up though menu activation (and getting it raised), or an SB-700/800/900.
It does however seem like your pop-up bit the dust, sorry to say.
If that is the case, it will not work as an illuminator flash neither as a commander.
Take this with a grain of salt, as I'm only starting to get my head around flash photography (real newbie), with a D7000 and an SB-700.
The simpler test you can do is switch the camera to all-auto mode, close yourself on a dark room and trigger the shutter. The pop up should rise and fire, if not it's proven faulty.
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