My pool is 36 years old and I just replaced the main 120 V Pool light last year, power cable, housing, buib and all.  The spa light has worked well for the entire 36 years.  Opened the pool this year and the spa light was out.  So, I figured, how long can a bulb last?  Took the bulb out and went to get a bulb at a pool supply store and also tried the local hardware store.  No luck.  In the hardware store, I asked the clerk to try the bulb out.  Worked!!!  OK, so back to my pool, put it all back together and tried it, no luck.  The main pool light is on the same GFCI and it works fine.  Opened the 'above' water line' connection box for the spa light, and I have 120 volts at the connectors.  So, what are the odds, the power cable for my light is open between that box and the spa housing?  I had it out to check the bulb and the cable looks OK.  I would hate to purchase one and find out it's OK.  Any ideas?