I've been having this problem quite a bit so I just know it's something basic.
I constructed a 3d space and tried to add particular to a layer and it just doesn't show up. The preview window shows what I want it to look like but when i scrub the timeline nothing! I've tried switching to 3d layers nothing works. I've attached a screenshot so I could be a bit more clear.
As you can see there is a white solid (that's 3d in this case) with particular applied to it. I used a pecomped white dot made in AE as the particle. (Since I'm going for a 70's sort of disco light refraction simulation by colorizing the white dot and having a series of them pass in front of the camera) BUT NOTHING HAPPENS. What can I do?