请教edtftpnet下载遇到的超时问题

[jiansheng123]

我要实现一个定时从FTP服务器下载文件到本地的功能，用的第三方类库是 edtftpnet，我是用一个timer,设置它的INTERVAL,每隔比如1分钟去从FTP的某个目录取文件下载下来，具体代码如下：

protected override void OnStart(string[] args)
{

MyTimer tmr = new MyTimer();

tmr.Interval = int.Parse(ds.Tables[0].Rows[i]["intervals"].ToString());
tmr.Directory = ds.Tables[0].Rows[i]["Directory"].ToString();
tmr.HistoryPath = ds.Tables[0].Rows[i]["historypath"].ToString();
tmr.Path = ds.Tables[0].Rows[i]["path"].ToString();
tmr.Type = ds.Tables[0].Rows[i]["type"].ToString();
tmr.Elapsed += new ElapsedEventHandler(tmr_Tick);
tmr.AutoReset = true;
tmr.Start();

}

private void tmr_Tick(object sender, ElapsedEventArgs e)
{

MyTimer _timer = (MyTimer)sender;

_timer.Enabled = false;

if (_timer.Type == "download")
DownloadFile(_timer.Directory, _timer.HistoryPath, _timer.Path);
_timer.Enabled = true;

}

public void DownloadFile(string DirectoryName, string HistoryPath, string Path)
{
FTPConnection ftpConn = new FTPConnection();
try
{

ftpConn.UserName = System.Configuration.ConfigurationSettings.AppSettings["UserName"];
ftpConn.Password = System.Configuration.ConfigurationSettings.AppSettings["Password"];
ftpConn.ServerAddress = System.Configuration.ConfigurationSettings.AppSettings["ServerAddress"];
ftpConn.ServerPort = int.Parse(System.Configuration.ConfigurationSettings.AppSettings["ServerPort"]);

ftpConn.TransferType = FTPTransferType.BINARY;

ftpConn.Connect();
ftpConn.WorkingDirectory = DirectoryName;
string directory = ftpConn.WorkingDirectory;
....
ftpConn.DownloadFile(Path, filetemp);
}
catch(Exception ex)
{

}
finally
{
if (ftpConn.IsConnected)
ftpConn.Close();
}
}


最后一直报错：System.IO.IOException: Failed to connect to 115.236.10.243:45663 within timeout 120000 ms
在 EnterpriseDT.Net.StandardSocket.InternalConnect(EndPoint remoteEP, Int32 timeout)
在 EnterpriseDT.Net.StandardSocket.Connect(EndPoint remoteEP, Int32 timeout)
在 EnterpriseDT.Net.Ftp.FTPControlSocket.NewPassiveDataSocket(String ipAddress, Int32 port)
在 EnterpriseDT.Net.Ftp.FTPControlSocket.CreateDataSocketPASVInternal()
在 EnterpriseDT.Net.Ftp.FTPControlSocket.CreateDataSocketPASV()
在 EnterpriseDT.Net.Ftp.FTPControlSocket.CreateDataSocket(FTPConnectMode connectMode)
在 EnterpriseDT.Net.Ftp.FTPClient.Dir(String dirname, Boolean full, LineCallback lineCallback, Object state)
在 EnterpriseDT.Net.Ftp.FTPClient.Dir(String dirname, Boolean full)
在 EnterpriseDT.Net.Ftp.FTPClient.DirDetails(String dirname)
在 EnterpriseDT.Net.Ftp.FTPConnection.GetFileInfos(String directory)
在 FTPService.FTPService.DownloadFile(String DirectoryName, String HistoryPath, String Path) 位置 C:\Code\FTPService\FTPService\FTPService.cs:行号 128

但是文件能下载下来，设置timeout属性也没用的，我已经试过了，请教高手这是什么原因