The first step is to unplug ALL the lights, this will check the circuit itself. If the breaker stays on then it is time to check each fixture.

Is this a circuit for these lights only?

Just read your other post. It would be easier if both posts were the same.

If just one light "popped" unplug that light and test. If the light is the culprit, replace it. I've found replacing is easier and about as cheap as fixing.

I've found replacing is easier and about as cheap as fixing.

Depends on the fixture. If it's one of the <$10 big box store cheapies, then that's about all you can do. If it's a "real" fixture with a replaceable ballast, then you (probably) change the ballast.

The cheapies seem to have about as high a failure rate as cheap retrofit compact fluorescents. You can't really buy a good fluorescent fixture for less than a sawbuck.

Thanks for your suggestions. Will unplug all the lights, attempt to reset breaker (single breaker for the 10 light fixtures), and see what happens. Will report. I sure was not thinking clearly when I asked for help..too hot here to think.
cella jane

I think you'll find a bad ballast. Any of your lights making excessive noise?