I got a similar error message, "%1 is not a valid Win32 application." HP advised me to retry the install as follows: 1. Restore the system to the last backup point (to ensure the system is "clean, i.e., with no residual system software changes from the HP install), 2. Uninstall any HP software by running batch file uninstall.bat from the HP CD, 3. Copy all the HP CD folders and files to a hard disk directory, 4. Run HP's setup.exe from the hard disk directory.