Simple Validation not working (sample attached)

[mendhak]

In a visually inherited form, I'm doing the following:

Overrides Sub Textbox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
        strTempVar = ""
 
        strTempVar = Me.TextBox1.Text
 
        If IsValid(strTempVar) Then
            Debug.Write("valid")
            Me.TextBox2.Text = strTempVar
        End If
 
    End Sub
 
 
Public Function IsValid(ByVal cstrTempVar As String) As Boolean
        If Len(cstrTempVar) < 10 Then
            IsValid = True
        Else
            IsValid = False
 
        End If
    End Function

Where textbox2 belongs to the new form only. It keeps breaking at the line:

Me.Textbox2.Text = strTempVar

When I move my mouse over Me.Textbox, the tooltip says Me.TextBox = Nothing

Anyways, it's a simple application, so I've attached it. Please tell me what I'm missing.