Timeout problem in FTPWebRequest

Hello Friends,
I write a VB application to download MLS feed files from MLS FTP server and import data into MySQL database. I used FTPWebRequest class to download files from the FTP.
Problem: FTP contains files from 30 to 500 MB size. My application stop working after downloading file upto 22MB and thereafter it hangs with no output or error.
Source code to download file from FTP:

Private Shared Sub DownloadFile(ByVal strHost As String, ByVal strPort As String, ByVal strUserName As String, ByVal strPassword As String, ByVal strDirectoryName As String, ByVal strFileName As String, ByVal intTimeout As Integer, ByVal strSaveDirectoryPath As String) Try Dim ftpURL As String = "ftp://" + strHost If strPort.Trim.Length > 0 Then ftpURL = ftpURL + ":" + strPort ...