I develop a program which connect to a web-server through network every thing works fine until I try to use some dongle to protect my software. the dongle has network feature too and it's API work under network infrastructure. when I added the Dongle checking code to my program I got this error:

"Either the application has not called WSAStartup, or WSAStartup failed"  

I don't have any idea what is going on?

I put the block of code which encounter exception here. the scenario I got the exception is I log in to the program (everything works fine) the plug out the dongle then the program stop and ask for dongle and I plug in the dongle again and try to log in bu I got exception on line

response = (HttpWebResponse)request.GetResponse();

DongleService unikey = new DongleService();

                checkDongle = unikey.isConnectedNow();

                if (checkDongle)
                {
                    isPass = true;
                    this.username = txtbxUser.Text;
                    this.pass = txtbxPass.Text;
                    this.IP = combobxServer.Text;
                    string uri = @"https://" + combobxServer.Text + ":5002num_events=1";
                    request = (HttpWebRequest)WebRequest.Create(uri);
                    request.Proxy = null;
                    request.Credentials = new NetworkCredential(this.username, this.pass);
                    ServicePointManager.ServerCertificateValidationCallback = ((sender, certificate, chain, sslPolicyErrors) => true);
                    response = (HttpWebResponse)request.GetResponse();

                    Properties.Settings.Default.User = txtbxUser.Text;
                    int index = _servers.FindIndex(p => p == combobxServer.Text);
                    if (index == -1)
                    {
                        _servers.Add(combobxServer.Text);
                        Config_Save.SaveServers(_servers);
                        _servers = Config_Save.LoadServers();
                    }

                    Properties.Settings.Default.Server = combobxServer.Text;
                    // also save the password
                    if (checkBox1.CheckState.ToString() == "Checked")
                        Properties.Settings.Default.Pass = txtbxPass.Text;

                    Properties.Settings.Default.settingLoginUsername = this.username;
                    Properties.Settings.Default.settingLoginPassword = this.pass;
                    Properties.Settings.Default.settingLoginPort = "5002";
                    Properties.Settings.Default.settingLoginIP = this.IP;
                    Properties.Settings.Default.isLogin = "guest";

                    Properties.Settings.Default.Save();
                    response.Close();
                    request.Abort();
                    this.isPass = true;
                    this.Close();
                }
                else
                {
                    MessageBox.Show("Please Insert Correct Dongle!", "Dongle Error", MessageBoxButtons.OK, MessageBoxIcon.Stop);
                }