This happens to me too, when using Poser 7 and PoserPro.
When I use Poser 6, I never get this issue. I've sometimes had Poser 6 open for an entire day, making all kinds of renders and it works fine.
But, if I use PoserPro for more than an hour (or less), I hit this "bug" and Poser disappears like the original poster said: no error message, no "Do you want to report this crash to Microsoft", just nothing.

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