You have changed the fuel pump fuel filter checked all the fuses and relays changed the spark plugs and coil the car wont start what else do you need to check or what else could it be?

I don't really know what kind of car do you have so I will just put it in genaral. I would check the distributor and the "ignition control modual".Sometime cleaning the air intake might help too ( just get the carburetor cleanner and spay it in while starting it..just to help it open and close better).