Another user had the same problem 2003.19.09 but got now help.
He wrote:

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Several actions in Outlook, including opening certain
types of attachments and copying e-mail addresses between
the CC: and To: fields of a message, cause the Windows
Installer to be invoked. Eventually, a "can't find patch"
error appears. officeupdate can't scan my machine and
suggests an issue regarding updating Windows Installer
from 1.0 to 1.1 but offers no resolution info.

Everything was installed w/admin priveleges.

Both Windows and Office are patched and totally up-to-
date.

Please help.

Thanks in advance.
*********************'

Anyone???