Sigma 28-300mm f/3.5-6.3 with nikon d60?

I owning nikon d60 and bought Sigma 28-300mm f/3.5-6.3 for Nikon, the lens says its auto focus but it is not working with nikon d60, any clarification, thanks in advance

The D60 only autofocuses lenses with an autofocus motor. Apparently, the Sigma lens you bought doesn't have one but it will autofocus with a Nikon body with its own autofocus motor. The D60 doesn't have one.
http://www.kenrockwell.com/...y-lens.htm
Take note of the spec page below for that lens. It clearly states in italics what I've mentioned.
http://www.bhphotovideo.com/...Macro.html
Quote -
"Note! AF not supported by D40, D40x, D60, D3000, D5000 cameras."

Just autofocus is not enough, unfortunately.
When a lens says that it's an autofocus lens, then this just means that it supports autofocus in general. That alone does not say yet how the autofocus is powered. In the past there usually was a autofocus motor in the camera body, which drives the autofocus in the lens using a screwdriver-like connection. You should be able to find such a connection at the rear end of your lens when you have it detached from the camera.
The D40, D40X, D60, D3000, D3100 and D5000 however do not have an own autofocus motor. They depend on the lens to have an internal one, such as Nikon's AF-S lenses, and also some Sigma and Tamron ones. These say in their description that they will autofocus with e.g. The D40.
So the one that you got (quite certainly a lens originally made for film SLRs, based on its specs) would autofocus on, say, a D90 with its autofocus motor, but not on your D60 without autofocus motor.

Apart from what the other answerers have already pointed out (regarding autofocus), my suggestion is to return this lens and instead get a 18-200mm Nikkor or something similar.
D60 is a crop sensor body and so you'll not get the 28mm angle of view with this lens.It'll be almost like a 40-45mm lens. Get a wider lens if you can.
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