Having a very tough time installing Parallels on my desktop Mac Pro. I have a Mac Pro, 4GB ram, 500GB hard drive. I installed Parallels using the EXPRESS method. Wasn't sure it was the best option, but it looked to be the easiest. The problem I have is that with a huge system like mine, Parallels seems to be limiting how much memory (RAM) and hard drive space I can devote to the program. I installed Parallels according to EXPRESS INSTALL. Vista installed fine. Got as far as installing my Internet Security and Antivirus. Vista had problems rebooting. It just sat there at the load screen. So, I went into tools and put in the maximum memory 1500MB. When I tried to start Parallels I got this message: "Unable to allocate virtual machine memory! This error may occur mostly if there is no enough free disk space available on the physical disk to allocate virtual machine paging file. Try to clean up the physical disk. If it doesn't help, try to re-install Parallels desktop." Can someone kindly instruct me how to max out all the necessary VIDEO and MEMORY areas effectively if I want 2GB RAM and 250GB hard drive space for Parallels? Note: I tried putting 250,000MB in the Hard Disk settings but it was much too high a setting for Parallels to handle. It will not let me put in anything above 128,000MB. On the Memory end, it will not let me go above 1500MB. Thank You!