How do I create a Data Validation formula for Column C? If a person tries to enter a number in Column C when an "X" is in a cell in Column B, would like a pop up box to open that says "Miles Not Allowed". I would prefer not having to create a VBA formula. Also, would I need two different formulas for Column C if a person enters a capital "X" or a lower case "x" in Column B?
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A | B | C |
Day | Vacation | Miles |
Mon | X | |
Tues | X | |
Wed | 200 | |
Thurs | 25 | |
Fri | 50 |
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