How do I make a rule that an identical number cannot be entered twice in an Excell column?
M Mark Mar 10, 2008 #1 How do I make a rule that an identical number cannot be entered twice in an Excell column?
B Bernie Deitrick Mar 10, 2008 #2 Mark, Say in a very deep voice: "Thou shalt not enter the same number twice in one column." ;-) Actually, use Data / Validation, with a custom formula of =COUNTIF(A:A,A2)=1 For column A, with A2 the currently active cell. HTH, Bernie MS Excel MVP
Mark, Say in a very deep voice: "Thou shalt not enter the same number twice in one column." ;-) Actually, use Data / Validation, with a custom formula of =COUNTIF(A:A,A2)=1 For column A, with A2 the currently active cell. HTH, Bernie MS Excel MVP
