One, has Windows recently updated?  The August 12 update has issues.  Check with MS site regarding what they suggest if your OS updated on August 12 and you are experiencing issues.

SMS tech support won't be of much help since they won't provide much if any support for P7.

Have your tried going into the prefs and deleting the Poser ini file?  When you uninstall Poser, do you run an app like CCleaner to clean up the uninstall before you try a re installation?