Validation.IgnoreBlank Property (Excel)
True if blank values are permitted by the range data validation. Read/write Boolean.
Syntax
expression .IgnoreBlank
expression A variable that represents a Validation object.
Remarks
If the IgnoreBlank property is True, cell data is considered valid if the cell is blank, or if a cell referenced by either the MinVal or MaxVal property is blank.
Example
This example causes data validation for cell E5 to allow blank values.
Range("e5").Validation.IgnoreBlank = True