I do not know what's wrong, although more than likely Sigma will be rechipping the lens and it will work fine when you (eventually) get it back.However, are you aware that even once it does power up, you won't be able to AF on the D5000? That camera requires in-lens focusing motors, which the Sigma 105 does not have.
_____Brian... a bicoastal Nikonian and Team MemberMy gallery is online. Comments and critique welcomed any time!
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