I just bought Photoshop CS4 extended for $2,400, and I must say that I am disappointed. I mean, I can't tell if the software itself is an improvement over the CS3 Extended, because I get this rather poorly worded answer. "The software cannot be installed because the file system of the OS volume is not supported. The OS volume should be local, writable, and should have a non-case sensitive file system." I was wondering, because this is ridiculously expensive software from a leading developer. I have honestly never seen this message from anywhere, until now. I believe that the message is telling me that I have to reformat my OS volume to match those specific details, or it will not install. Does anyone know how to install without reformatting my OS drive? Thanks.