Unlock Specific Cell if another cell in row has specific value

[EAB1993]

I have been trying to find a macro that will unlock a cell in Col BA if the corresponding cell in Col I has the marker "M". But to remain locked if there is any other value in Col I. I have not been able to find one that works without giving me errors or unlocking too much.

 

[EAB1993]

Private Sub Worksheet_Change(ByVal Target As Range)

If Range("I4").Value = "M" Then
ActiveSheet.Unprotect ""
Range("BD4").Locked = True
ElseIf Range("I4").Value <> 0 Then
Range("BD4").Locked = False
ActiveSheet.Protect ""
End If

End Sub



This is what I have tried that doesnt work