Just recently, I have started having a problem where when I change the lights in the room to anything other than the default, the program crashes when I try to render the image. If I leave the default lights, there's no problem. And I didn't always have the problem... it's just started in the last week. Help!

Are you using Poser 5?

As a start, the following details will help: Poser version (including full version number) Operating System. System RAM. I've found that sometimes quite trivial-seeming changes to a scene can hit RAM limits on my system. A consistent change of behaviour could be a sign of a virus or trojan, lurking and using a bit of RM. I know that there were utilities which could clean out the Windows Registry, which can gradually grow. A utility which displays memory use can be informative, and frightening. OK, I'm guessing, but hitting the physical RAM limit can really mess with how Poser runs. My experience, it's the first thing to look to.

I've had that happen with RDNA lights with a heavy scene. No problems using Daz globals in heavy scenes though.

If it's the same scene involved every time, you might try deleting bump maps and reflection maps one-by-one. I've had bad references choke Poser to a crash on render in the past.

It was a different scene each time, they weren't RDNA, they were Daz lights, and from what I can see there's no great depletion of RAM from the system. I run some very intensive programs, and I haven't had any trouble with them. Just this one feature of Poser.

I've found in P5 that deleting all lights from the scene before loading a new set can avoid this. Ockham has a python script in freestuff that will do this.