Hi folks,

I'm using a piece of code to Data-Validate a couple of columns and it keeps falling over with the error message:
Run-Time Error '-2147417848 (80010108)': Automation error. The object invoked has disconnected from its clients.

The code stops at the red line below:

Private Sub Data_Validate()
Dim FirstWS As Integer, LastWS As Integer, M As Integer

FirstWS = 6
LastWS = 12
For M = FirstWS To LastWS
    With Sheets(M)
        With Columns("C:C").Validation
            .Delete
            .Add Type:=xlValidateWholeNumber, AlertStyle:=xlValidAlertStop, _
            Operator:=xlLessEqual, Formula1:="41"            
            .IgnoreBlank = True
            .InCellDropdown = True
            .ErrorTitle = "Leave Programme"
            .ErrorMessage = "You must enter a numeric value"
            .ShowInput = False
            .ShowError = True
        End With
        With Columns("B:B").Validation
            .Delete
            .Add Type:=xlValidateDate, AlertStyle:=xlValidAlertStop, Operator:= _
            xlBetween, Formula1:="4/1/2008", Formula2:="3/31/2009"
            .IgnoreBlank = True
            .InCellDropdown = True
            .ErrorTitle = "Leave Programme"
            .ErrorMessage = _
            "Ensure that the date entered is between 01/04/2008 and 31/03/2009"
            .ShowInput = False
            .ShowError = True
        End With
    End With
Next M

End Sub
Can anyone enlighten me why this happens, please?

Seamus