If you have Zone Alarm 3 or Zone Alarm 3 Beta running disable them and run the setup of PowerDesk PRO 5 again. If you are unfamiliar on how to do this or if this does not solve the installation issue you can run the install from Safe Mode. You can get to Safe Mode by restarting your PC and tapping the F8 key. At the Windows Start Menu choose option 3. Once your desktop has finished loading, locate the installation file (PDPRO50.EXE) and double-click.