RemoteCalendars is a plugin for Outlook 2003, so it DOES actually need
Outlook 2003
However, what's is needed is the Outlook 2003 PIA to be installed (if
you did upgrade fro Outlook 2003 to 2007, RC works because you could
install them)...unfortunately, they can be installed only when Outlook
2003 is installed
And I havem't found a solution yet.