Deep in the archives there was a solution for ProPak but I don't know if it would work for P5. The jist of it is, run scandisk then remove the swap file and from the safe mode run the de-frag. Now here's the part I'm not sure of with P5: move your runtime to another drive and re-install Poser( plus sr's). Now burn the 8 or so main files to cd, use as emergency. Re-set your swap and re-boot. Move runtime back. I used my emergency cd for just this thing on PP- let it overwrite the files and all was well.

I must remember to remember what it was I had to remember.