For some computers, the Update "Rollup" is required..Try clicking on the link below, then installing the Win98 Rollup from the link provided on the page:
http://support.microsoft.com/kb/889669
After you've installed this rollup, go back to Windows Update and see if it's fixed.
Hope this helps.
Grif
After downloading and installing "Cumulative Security Update for Internet Explorer 6 Service Pack 1 (KB889293)", it's still listed as an available critical update on the windows update site. Thanks, John. Win98se IE6sp1

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