Thank you Paul. They're not exactly the same, and Office Starter has not been activated. This should not cause an invalid product key in Pro Plus. I spoke with a rep from Microsoft yesterday, and she agreed, however she could not understand why I was getting an invalid product key message for Pro Plus, as she was able to verify that I had the program installed and activated. The only way for Microsoft to help me further was to transfer me to a support rep, and for me to pay $49 for it. I am reluctant to uninstall Starter until I know that Pro Plus is OK, and I am reluctant to uninstall Pro Plus and do a reinstall due to the issue with the invalid product key that I'm getting. I never got that message before.