Hi Allex,

This is how I solved this, I force my users to enter the month alphabetically.

        Dim cDS As String = DateTimeFormatInfo.CurrentInfo.DateSeparator
        Me.Mask = "##" & cDS & "aaa" & cDS & "##"

For Dutch I use the following validation (at this stage, I only support dutch at this stage)

    Public dateFormat As String = "dd/MMM/yy"

    Function checkDate(ByVal c As String) As Boolean
        Dim d As Date
        Return Date.TryParseExact(c, dateFormat, CultureInfo.CurrentCulture, DateTimeStyles.AssumeLocal, d)
    End Function

>Thank for your reply me ,but i have some problem.........
>If the user region setting is Date format (DD/MM/YY) then , eg. (13/02/11)
>
>but if the user region setting is Date format (MM/DD/YY) eg. (13/02/11), will error in isdate function, so how can i do ,
>in isdate function convert the Maskedate.Text to do checking, base user region setting date format?
>
>

>Dim dateEntered As DateTime
>        DateTime.TryParse(Maskedate.Text, dateEntered)
>
> If IsDate(Maskedate.Text) = False Then
>            MsgBox("Error available date !", 48, "Warning")
>            Maskedate.Focus()
>            check = False
>            Exit Sub
>
>