We have had this problem when users have manually added the those files as add-ins to Excel to use formulas in the previous version.
With Excel add-ins, just locate the file and delete it or rename it (if you have access to). When you re-open Excel, it will say something about being unable to locate the file, then go to add-ins and Excel add-ins and uncheck. This will remove it permanently.
Please note, this is not recommended for COM Add-ins! ;-)
James
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James McCarthy
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