Windows XP Error Code 0x80070643

The following updates will not install on
my computer (running Windows XP).
Office 2003 - Update for Office 2003
Office 2003 - Update for Microsoft Office Outlook
2003 Junk Email Filter (KB2553111)
Office 2003 - Office 2003 Service Pack 3 (SP3)

Installation Failure - Error Code 0x80070643

If there are more Updates, they will install
fine. I.E at shutdown indications are for
3 updates. next shutdown - same 3. If indications
at shutdown are 5 updates, 2 will install but next
time the same 3 updates appear

I have contacted Windows Update and tried their
suggestions to fix the problem. Each time I go
to the Update site, I get a different suggestion.
None have worked. :confused