hi tom, below alterations in your code helped me....
Dim Answer As String
ReTry:
Answer = InputBox("Please enter the date in the following format: dd-mm-yyyy", "Enter Date", Format(Date, "dd-mmm-yyyy"))
If Answer = "" Then Exit Sub
Answer = Format(Answer, "DD-MM-YYYY")
'valid dates will be 1900 to 2099. Edit to extend the range
If Not IsDate(Answer) Or Not Answer Like "[0-3]#-[01]#-[12][09]##" Then
If MsgBox("Invalid date or invalid date format. " & _
"Please enter the date in the correct format.", vbRetryCancel) = vbRetry Then
GoTo ReTry
Else
Answer = Format(Answer, "DD-MMM-YYYY")
Exit Sub
End If
End If