If it's the correct bulb, it's not longer than the fixture. Look at the list on the back of the light and the corresponding number on the box the bulb came in and make sure it's the right one. You have to stick one end in and push down, then then the other end will slide in. Make sure you don't touch the bulb with your bare fingers.

Don't be afraid to push the bulb down on the spring. It does require some effort, but do it once and you'll get the hang of it.

Clean the bulb (oily)?
 

Thank you very much, but I have already touched it with my bare fingers quite a bit. Matter of fact, I touched the other two lights in the DV kit that I purchased. What should I do now? Try to clean them or something? And yes it is definitely the right bulb.

Thank you very much for helping,

Trey Vollmer

Take a soft cloth and thoroughly wipe the lamp (bulb). You could use a little windex, vinegar or amonia on a damp cloth if the lamps are smeared up.

The problem is that grease from fingers gets on the lamp (bulb). Grease holds more heat and gets hotter than the glass. This creates a hot spot, with gets weak. The lamp explodes out through this weak spot.

Which is a reminder that the protective screens must be used if the lights are turned in any way whereby an exploded lamp could cause hot glass to hit someone.

Which installing the lamp, hold it with a piece of cloth or other protection. Thin white gloves sold at film equipment supply houses work will. You can keep a couple of these cheap gloves in your light case. Also a little piece of cotton cloth, the protective foam that comes in the lamp package, or similar also work well.

I always use the piece of foam the lamp is wrapped in, but any piece of cloth will do if you've already pitched the foam. Never tried cleaning a bulb that somebody touched before, but Windex is probably a good idea. I'd also keep an eye on the lamps and if you see a small bubble forming after a few hours use, pitch it because it will explode eventually. I've only seen one quartz light explode, and it was a 1K bulb. Shot molten glass about 10 feet across the room and burned little holes in the carpet. All open face lights come with protective scrims today but even so, small pieces of hot glass can escape. That's why museums and art galleries are so picky about what kinds of lights you use.