I'm not sure why, but recently when I render in Poser 7, if I have a background image in the picture, the background will render but when I go to export the image to a PNG file, the background image disappears. This has only started recently, and I don't know what I did to make it so that the background will not export. Does anyone have any clue what I need to fix? I have the render setting set to render over background image, yet it acts like it's rendering over black. I don't know what to do.

Is the background still black when loaded into a paint program?

No, the background is completely gone. Like when I open the rendered PNG file in Photoshop, everything is there against a clear background. I mean, I can just slide the background underneath no problem, but half the time I can't remember what background I used to begin with, which is why I like to render the background with the rest of the picture. But as I said, I can't do that any more. I just want to know what to click to change that.

It sounds like a bug in poser 7, you could try rendering to bitmap ,bmp and then converting it to a png.

TIF is also a good bet, and is loss-less in the same way that bitmaps are, but with some file compression built in.