A validation need --- Excel VBA (Macros)

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim r As Range, msg As String
    If Intersect(Target, Columns(1)) Is Nothing Then Exit Sub
    Application.EnableEvents = False
    For Each r In Intersect(Target, Columns(1))
        If r.Value <> "" Then
            If Not r.Value Like "V-[A-Za-z]####" Then
                MsgBox "Invalid Entry", vbCritical, r.Value
                r.ClearContents
            End If
        End If
    Next
    Application.EnableEvents = True
    If Len(msg) Then MsgBox msg, , "Invalid entry"
End Sub

I guess you can't apply the code, so attach a workbook showing where(range) to apply.