When I double click on a xls or doc file

[JJ]

When I double click on an Excel file or word file it seems
that it is tring to open twice. I get this message:
A document with the name "filename" is already open. YOu
cannot open two documents with the same name, even if the
documents are in different folders.
To open the second document, either close the document
that is currently open, or rename one of the documnets

I even tried to just select it and hit enter.
It will work if I am in word or excel and use the file
open command.

any clues!!
..