When trying to install my developer preview for 10.7 Lion, I receive the following message after about 99% of installation: "An error occurred while preparing the installation. Try running this application again. If the problem persists, go to the computer with the Mac OS X Install DVD, open Remote Install Mac OS X (located in the Utilities folder in the Applications folder) and follow the onscreen instructions for restarting your computer using the DVD When the Mac OS X Installer opens, follow the onscreen instructions to install Mac OS X." I already tried to reformat the entire harddrive and checked it with disk utility. Anybody can help me? Tanks a lot!