Users need to be watch the screen carefully when entering data. If you enter, say, A* into one cell and then A into another cell, for the second entry Excel will change the A to A* with the * highlighted. If you just continue, Excel will replace the A with A* without warning. Therefore, entering data without looking at the screen can result in having the wrong data. Of course, you can turn off Excel's automatic correctionj facility (although I don't know how to do that yet). Would be better for Excel to default to what is actually typed though or at least ask permission to change data.
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