This issue was noted with Excel 97 and Windows XP and versions of Outlook. There is no cure for that one.
The workaround is to save the Excel sheet and then open it.
Bob
Why can't I open Excel attachements (not Word, PDF's, etc.) by double clicking.If I do, it launches Excel but not the file. Only if I save it first, can I then open it up? I'm very frustrated!

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