Office 2000 installed? / not installed?

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I HAD installed office 2000 pro in my computer,
then I go to officeupdate website to check for my updates

It highlight SR-1a and let me download the express install program.
After I download and open the file, the dialog box state that I did not
install any office product in my computer............

But I can use Word, Excel..........>>>>>> Office Is Installed.....
I've also try to download the whole package and then install the sp
but with the same error
So, what can I do?

Thank you very much

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