Open up the particle file in notepad and see what the bubble is actually called there. At the top it says
"particle_system [particlename]". Try typing where it says the particle name into your particle box.
The reason I have you do this is because sometimes the person who creates a particle will have multiple variations of that particle (one that goes up, to the right, to the left, etc.) They'll name the particle file "FireFly" for example, but what you'd actually have to type into the particle maker is "FireflyEast", "FireflyUp", etc. which can only be found by opening particle file itself in notepad.