Try fitting a new bulb. If the light then works you know it's the bulb that was faulty.
If it still doesn't work then you've got a problem elsewhere- somewhere between the light switch and the non-working bulbs. Could be the wiring connection coming loose on the light fitting but rather unlikely.
Peter B, November 2010
you cant tell by just looking you need to check the bulbs with a meter,or try them in the fitting that works,
it can only be two things,the bulbs,or the transforner
mm, November 2010
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I can answer this question...
i have four halogen down light under my kitchen cabnet 2 are still working ?