Hi,

This should be an easy one. I want to display an error message when the
cell that has the speed formula (Miles / Hours) exceeds 515 mph or is below
440 mph. I have not had success with the data validation route. With IF
statements I can get error messages in the cell, but Id really like and
error dialog box to pop up so the user is forced to correct the error or give
rational for the unusual speed.

Im a novice that doesnt know VBA, so I pretty much need step by step
instructions.

Thanks In Advance,