Validating a cell

Originally Posted by m.cain

Thank you for your reply and useful link.

How does this work though if you have more than one cell that you want un-editable if the first cell does not have the correct value?

e.g. Cell 1 = ""
Cell 2 = ""
Cell 3 = ""
....

while:
Cell 1 = "X"
Cell 2 = "1, 2, 3"
Cell 3 = "red, blue, green, yellow"
...

If cell A1 contain the optoin of X or blank
Then apply Custom Data Validation in A2 as

=AND(A1="X",OR(A2=1,A2=2,A2=3))

remember to uncheck the Ignore blank option.

And in cell A3 use this Custom formula

=AND(A1="X",OR(A3="red",A3="blue",A3="green",A3="yellow"))

remember to uncheck the Ignore blank option.

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formulas wrapped