excel won’t show spreadsheet

This is a stumper! when opening a .xls file by double-clicking on the file, Excel launches, but won’t show the sheet – it simply shows a blank grey area below the formula bar. It will open anything normally from its own File|Open command.

Files are associated properly; version is office 2000 SP-3, and it has been repaired and then reinstalled, and still does the same thing.

Any clues?