Hey Hambo,
I had exactly the same problem with no access to my original XP CD, nor a system restore point to get rid of the damn SP3.
Credit 'Steven Hawkins' for this fix which worked for me...
Inspection of the Event Log gleaned the information that Excel failed to
find 'XLStart', and it turned out that simply adding an XLStart folder to
the Office\ and Office10\ folders list, immediately created the personal
XLStart folders for each user, and enabled Excel to update to SP3 with the
other programmes.
Having said this, running the Office Update from scratch still gets stuck at
'where's PRO.MSI', but at least the major components now seem to be working.
Regards,
SteveH
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