Class not registered accessing Archive Explorer

I have one user who receives the error "The XML page cannot be displayed. Class not registered" when trying to access Archive Explorer from Outlook or through IE 32-bit. It works fine using IE 64-bit. No on else is reporting the issue and the same account works fine from another computer. I've tried resetting IE settings, uninstalling/reinstalling the EV client, using another windows/archive account, resetevclient, etc. Any thoughts? Windows 7 64-bit Outlook 2010 EV 10.0.3 Lync 2010