This was the response from Tech Support. They read my mind regarding installing to a clean directory. It now works with SR4, although I have not copied my Runtime directory over yet. I'm going to do that soon. For those having the same problems I'm having, hope this works for you! Russ Here's the complete text that I got this afternoon: "I'd recommend trying to install Poser to a new directory and update that version. The uninstaller will only remove files that it installed, so newly created files (preferences and such) and added content aren't removed when you uninstall. If any of these files are damaged they can still be problematic for the new installation. I would suggest going right to the SR4 updater, but certainly if you would like to be cautious you could try SR3 first. Once that is running succesfully you can perform the SR4 update again. When you get a copy running in the new directory you can integrate the old content in a couple of ways. You can use the multiple Runtime support of Poser 5 to dynamically link to your older Runtime. To do this click the "Up" arrow at the top of any library until you reach the top level. You can then click the "+" at the bottom of the library to add a new Runtime. Double-clicking any of the listed Runtime directories will load the contents of that Runtime for the current library. If you use this method for accessing all your content I would recommend manually deleting every except the Geometries, libraries, and Textures directories. If you anticipate using this method it might also be a good idea to choose the Minimum installation when installing Poser 5, or select Custom and pick only the new Poser 5 content. This will help avoid having alot of duplicate content using up drive space. The other way of integrating the legacy content would be to simply move the older Runtime into the new Poser directory. The two Runtimes will be merged, however newly installed files will be overwriten by the older ones. Again I would recommend deleting everything except Geometries, libraries, and Textures directories before merging. This will prevent updated resource files from being overwritten by previous ones. Lastly, (with tongue partially implanted in cheek...) by all means please do move Poser to XP!! More seriously, it would be a good test to install Poser on the other machine. Note that the license allow installation of the software on any number of machines. It only prohibits running it simultaneously on mutiple machines. There would be no problem having it on each."