Loaded Photoshop Elements 9 on a computer that is not on the internet and works fine as long as the user logging into the computer has admin privileges but a user who does not have admin priviledges gets an Error:6 that says to uninstall and reinstall the product. Uninstalling and reinstalling the product has no effect. I believe this to be that the normal user doesn't have permissions to a file somewhere that it needs to write to but can't seem to locate that file as I have given write permissions to Adobe under Programs & Common Files but no success.
first try restoring preferences to their defaults: http://help.adobe.com/en_US/PhotoshopElements/9.0/Using/WS3427C0BF-03F 8-421b-8CDF-6AC4D42C9983_WIN.html
What happens if you change the properties of PSE Editor as well as Organizer to always run with admin privileges. Right click on the respective exes in Program File >> go to properties >> tick the checkbox corresponding to "always run with admin privileges".
See if this makes any difference.