The copy protection can cause these sorts of problems, although it doesn't for everyone. As Stewer says it was removed in SR4.1 (in fact any SR > 2.1). But you can still install the copy protection "inadvertently" if you start Poser 5 - particularly an old copy of P5 - BEFORE you apply the SR. The copy protection scheme is executed when you first start P5, so apply SR4.1 first after installing P5, then start Poser 5, and all should be well. If you have already got Interlok code running on your system, then you'll need to scan the Web for instructions on how to remove. (There were some here on Renderosity, but Pace have removed some of the tools used in that method used.)