First, as Crimedog suggested, insert a blank column B
Then I would do this in two parts. First write a worksheet event code for doubleclick (paste this code into the worksheet vba window)
Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
If Target.Column > 1 Then Exit Sub
If Target.Interior.ColorIndex > 0 Then 'if the target already is colored
Target.Interior.ColorIndex = -4142 'remove the color
Target.Offset(0, 1) = "" 'clear the cell in col B
Else
Target.Interior.ColorIndex = 14 'set the background color to green
Target.Offset(0, 1) = 1 'set the cell in B to 1
End If
End Sub
This code will color your cell (adjust the color index for a specific color (1 to 56 I believe) and will put a 1 into column B of that row.
Then in Column C and over, you can use VLOOKUP function inside an IF statement to look in Column B, if there's a 1, then do a vlookup, if not, keep blank. If you need help with VLOOKUP, let us know.
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