As well as having to set the correct drive letter if Drive "c" is not used, 
BECAUSE OF THE MANY VERSION OF OFFICE, YOU MIGHT NEED TO CHANGE THE ADD-IN INSTALL FOLDER AS WELL.

NOTE: These changes might need to be made during the second part of the installation.

The default Add-In folder is for OFFICE XP/2003, which is ...
C:\Program Files\Microsoft Office\OFFICE11\STARTUP

For the next version of OFFICE, the folder needs to be set to ...
C:\Program Files\Microsoft Office\OFFICE12\STARTUP

For OFFICE 2000, the folder needs to be set to ..
C:\Program Files\Microsoft Office\OFFICE10\STARTUP

For OFFICE 97, the folder needs to be set to ..
C:\Program Files\Microsoft Office\STARTUP





