I installed it on XPHome too, so far no problems (I only installed it this morning). I don't see how a program like this can crash Windows completely, it does indeed sound like something else is wrong and that it's just a coincidense that it happened when you installed the patch. Also since the Restore didn't work it sounds like some virus to mee :o(

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.