Undeclared Variable [solved]

Public Class Form1 

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick 
  Dim max As Integer = 5000 
  Dim rnd As New Random 
  Dim rand As Integer = rnd.Next(10, max + 1) 
  Dim i As Integer = 1 
  Dim number(max - 1) As Integer 

  For i = 0 To max - 1 
    If number(i) = rand Then 
    rand = rnd.Next(1, max + 1) 
    i = -1 
    ElseIf number(i) = 0 Then 
    number(i) = rand 
    rand = rnd.Next(1, max + 1) 
    If i = max - 1 Then 
    Exit For 
    End If 
    i = -1 
    End If 
  Next 
  Timer1.Interval = number(i) 
  i += 1 

  ChangeImage() 
    End Sub 

    Private Sub ChangeImage() 

  Static Dim iImage1 As Integer 

  Select Case iImage1 
    Case 0 

    pbNewImage.Visible = True 
    pbNewImage.Image = My.Resources.DSC00002 
    iImage1 += 1 
    Case 1 

    pbNewImage.Visible = True 
    pbNewImage.Image = My.Resources.DSC00831 
    iImage1 += 1 
    Case 2 

    pbNewImage.Visible = True 
    pbNewImage.Image = My.Resources.DSC01760 
    iImage1 += 1 

  End Select 

    End Sub 
End Class