I'm trying to modify validation for adjacent celss on the fly depending on
the value of the previous cell. I've got this code but it is throwing an
error.

?????


If ActiveCell.Offset(0, -1).Value = "D" Then
'Range(Myaddress).Validation.Modify (xlValidateDate,
xlValidAlertInformation, _ xlBetween, ="1/1/2010", ="12/31/2020")

Endif