Or for the fun of it you can leave the errors as they are and highlight the cells with the formulas, set the font to white; then format the cells with [black]#,##0_);[red](#,##0) etc. This way erros will still exist they will not show and any valid result will.
[COLOR=blue white]I am posting this, just as an alternative that exists.
My preference is to go with what Messers Higgins and Wright have suggested.[/color]
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