I have the following:

Protected Sub GridViewAttachments_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridViewAttachments.RowCommand
        If e.CommandName = "Browse" Then

            Dim myConnection As New SqlConnection(ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString)

            Dim index As Integer = Convert.ToInt32(lblInterviewID.Text)
            Try

                Dim ds As New DataSet

                Dim da As SqlClient.SqlDataAdapter

                Dim arrContent As Byte()

                Dim dr As DataRow

                Dim strSql As String
               
                strSql = "Select * from [tbl_dotnet_attachments] Where [AttachmentID]='" + e.CommandArgument.ToString() + "'"

                Dim myCommand As New SqlCommand(strSql, myConnection)

                da = New SqlClient.SqlDataAdapter(strSql, myConnection)

                da.Fill(ds)

                dr = ds.Tables(0).Rows(0)

                arrContent = CType(dr.Item("ImageContent"), Byte())

                Dim filePath As String = dr.Item("Filename").ToString()

                Dim dotPosition As Integer = filePath.LastIndexOf(".")

                Dim filenameOnly As String = filePath.Substring(dotPosition + 1)

                Select Case filenameOnly
                    Case "zip"
                        Response.ContentType = "application/x-zip-compressed"
                    Case "pdf"
                        Response.ContentType = "application/pdf"
                    Case "csv"
                        Response.ContentType = "application/csv"
                    Case "doc"
                        Response.ContentType = "application/doc"
                    Case "docx"
                        Response.ContentType = "application/docx"
                    Case "xls"
                        Response.ContentType = "application/xls"
                    Case "xlsx"
                        Response.ContentType = "application/xlsx"
                    Case "png"
                        Response.ContentType = "application/png"
                    Case "gif"
                        Response.ContentType = "application/gif"
                    Case "jpg"
                        Response.ContentType = "application/jpg"
                    Case "csv"
                        Response.ContentType = "application/csv"
                    Case "txt"
                        Response.ContentType = "application/txt"
                End Select

                Response.BinaryWrite(arrContent)
                Response.Flush()
                Response.Close()



            Catch ex As Exception

         
            End Try



           
        End If

    End Sub

it fails when I try to write the binary content.