Sometimes one of these works:

Tools|Options|General|Ignore other applications (uncheck it)

--- or ---

Close Excel and
Windows Start Button|Run
excel /unregserver
then
Windows Start Button|Run
excel /regserver

The /unregserver & /regserver stuff resets the windows registry to excel's
factory defaults.

Arrow Computer wrote:

Clicking any .XLS file opens Excel 2003 but doesn't find the file, error reads:
Windows cannot find 'path\filename.xls' ...
The paths and files do exist as I can open them from File | Open
--
Arrow Computer Services

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Dave Peterson