How to Automate NAVIS – The Blog Pros

Hi DW, I'm trying to automate using NAVIS, I tried using post method simulating how it does on a web browser but I get error 678 then now I'm trying to access it using vb.net web browser.It does load but the issue is that I can't set the input elements value automatically using this code
WebBrowser1.Document.GetElementById("iNfYj").SetAttribute("value", "Testing")
this line of code is inside a button on my form.
Heres how I load the page on form load

Private Sub frmMenu_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        WebBrowser1.Navigate("http://41.162.72.195:9080/apex/capHomeView.zul")
    End Sub