I'm using Max 09 32bit (no SP1, not sure if it matters but I'm a bit afraid of updating mid project unless I have to) Windows XP, and I'm using particle flow for 3 different particle flow sources. I've got two for bubbles and one for lava lamp type bubbles.
They all work fine, but whenever I reload my scene, one of the bubbles PF sources disappears as if I've disabled the "Enable Particle Emission" option for that particular PF Source. When I render they don't show up. I have to disable the particles then re-enable them every time I reload the scene. I've tried messing around with different options and resaving it, but it keeps doing it. The other two PF sources work perfectly fine, but this one doesn't for some reason.
This is getting really frustrating too. Any ideas what's causing this? I haven't been able to find any other info on this, so obviously it's just my own silliness here!