i was installing an antique ceiling light which has 4 up lights and 4 down lights. One pair (i.e. one up and one down) doesn't work. When I tried tightening the two bulbs, thinking that perhaps they weren't fully seated, I got a shock. (Note: All of the bulbs were hard to get into the sockets, probably because it's a very old fixture. I had to turn them to the point where i was worried about breaking the bulb.)

I'm guessing there is a short or lose wire somewhere??

Can anyone suggest how to go about checking/fixing it and what I should be looking for? Do i just need to take apart and check that one socket for a lose wire?

Believe it or not, I just spent $200 at a specialty lighting shop to check the fixture and get it ready for hanging. You think they would have checked it too -- which they claim they did. But anyway, it's too much work to take it down and back to the store.

Thanks