I downloaded the Office 2007 Professional trial--"disk 1" and "disk 2".
However, when I install the trial version, Outlook is blocked out (with the
red "X"). Everything else installs just fine, but Outlook says it is not
available.

I'm running Office Pro 2003 on Windows XP SP2 (all up-to-date according to
Windows Update).

Is there a step or a piece of software I am missing?

If I purchase the software in a box, will this problem go away?