SymptomsYou are trying to install Parallels Desktop on the Mac with 10.4.x Tiger OS and receive the error:
"Parallels Desktop can be installed on Intel-based mac only"
blocking the installation. In the System Profiler (Applications -> Utilities -> System Profiler) you verify that the Mac has Intel processor:
CauseMost probably Installer.app binary file which runs Parallels Desktop installation has the option "Open using Rosetta" enabled:
Resolution1. Find the installer.app file: /Applications/Utilities/Installer.app
2. Right click (ctrl+click) on the file and choose 'Get info'
3. Uncheck the option "Open using Rosetta"