How do i fix a System.StackOverflowException on visual basic 2008?

[Joshua]

I have hit a System.StackOverflowException on my webbrowser application in visual basic 2008.

My code is as follows:

Private Sub MDIParent1_FormClosing(ByVal sender As Object, ByVal e As_ System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
Try
SW = System.IO.File.AppendText(History)
For a = 1 To ComboBox1.Items.Count
SW.WriteLine(ComboBox1.Items(a))
SW.Flush()
Next
SW.Close()
Me.Close()
Catch ex As Exception

End Try
End Sub

I really have no idea how to fix this. it is used to write the history to a .hst file for later acces by the webbrowser.

I could really use some help please.