Outlook 2003 cannot Word 2003

[B Simon]

I installed Office 2003 Pro on a machine with Office XP
choosing the "upgrade" option. When I try to compose a
message in Outlook, it complains it cannot find or Word or
it is the wrtong version and it unchecks the option to use
word for mail. If I recheck and actually start Word first
by hand it is fine but if Word is not running I get the
same behavior.

I've tried uninstalling Office XP, using the Repair option
and even a full reinstall of Office 2003 (since i assume
it is a bad registry entry) but no luck.

Any suggestions on how to cure this?

Thanks: Barry