I am currently Developing an anti-Cheat program for Counter-Strike 1.6 and I am having a problem with the Button3_click whenever i click that button to upload the "file" to the server it crashes and gives me this error.

An unhandled exception of type 'System.UriFormatException' occurred in System.dll Additional information: Invalid URI: The format of the URI could not be determined.
Code:
Public Class Form1


    Private Sub Label3_Click(sender As Object, e As EventArgs) Handles Label3.Click
        Application.Exit()

    End Sub

    Private Sub Label4_Click(sender As Object, e As EventArgs) Handles Label4.Click
       Me.WindowState = FormWindowState.Minimized
    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        Dim bounds As Rectangle
        Dim screenshot As System.Drawing.Bitmap
        Dim graph As Graphics
        bounds = Screen.PrimaryScreen.Bounds
        screenshot = New System.Drawing.Bitmap(bounds.Width, bounds.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)
        graph = Graphics.FromImage(screenshot)
        graph.CopyFromScreen(bounds.X, bounds.Y, 0, 0, bounds.Size, CopyPixelOperation.SourceCopy)
        PictureBox1.Image = screenshot
        Dim savefiledialog1 As New SaveFileDialog
        Try
            savefiledialog1.Title = "Save File"
            savefiledialog1.FileName = "*.bmp"
            savefiledialog1.Filter = "Bitmap |*.bmp"
            If savefiledialog1.ShowDialog() = Windows.Forms.DialogResult.OK Then
                PictureBox1.Image.Save(savefiledialog1.FileName, System.Drawing.Imaging.ImageFormat.Bmp)

            End If
        Catch ex As Exception

        End Try
    End Sub

    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
        Dim request As System.Net.FtpWebRequest = DirectCast(System.Net.WebRequest.Create("server28.000webhost.com/public_html/config.cfg"), System.Net.FtpWebRequest)
        request.Credentials = New System.Net.NetworkCredential("a7977306", "PASSWORD")
        request.Method = System.Net.WebRequestMethods.Ftp.UploadFile
        Dim file() As Byte = System.IO.File.ReadAllBytes("C:\Program Files\Steam\steamapps\payne38\counter-strike\cstrike\config.cfg")
        Dim strz As System.IO.Stream = request.GetRequestStream()
        strz.Write(file, 0, file.Length)
        strz.Close()
        strz.Dispose()
    End Sub
End Class