'System.Net.Mail.SmtpException: Failure sendin

i tried to send mail from a VPS windows 2012 & IIS 8 server using a remote mail server , i couldn't sent mails,and got the error

send Faild - System.Net.Mail.SmtpException: Failure sending mail. ---> System.Net.WebException: Unable to connect to the remote server ---> 
System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time,
or established connection failed because connected host has failed to respond <Ip Address> at System.Net.Sockets.Socket.DoConnect(EndPoint 
endPointSnapshot, SocketAddress socketAddress) at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6,
Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception) --- End of inner exception stack 
trace --- at System.Net.ServicePoint.GetConnection(PooledStream PooledStream, Object owner, Boolean async, IPAddress& address, Socket& abortSocket,
Socket& abortSocket6) at System.Net.PooledStream.Activate(Object owningObject, Boolean async, GeneralAsyncDelegate asyncCallback) at     System.Net.ConnectionPool.GetConnection(Object owningObject, GeneralAsyncDelegate asyncCallback, Int32 creationTimeout) at     System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint) at System.Net.Mail.SmtpClient.Send(MailMessage message) --- End of 
inner exception stack trace --- at System.Net.Mail.SmtpClient.Send(MailMessage message) at WebApplication1.Default.Page_Load(Object sender, EventArgs e)

code used

<%

Dim Email As New System.Net.Mail.MailMessage( _"emails@domain.org", "email@domain.org")
Email.Subject = "test subject"
Email.Body = "this is a test"
Dim mailClient As New System.Net.Mail.SmtpClient()
'This object stores the authentication values
 Dim basicAuthenticationInfo As _
New System.Net.NetworkCredential("username", "password")
mailClient.Host = "host"
mailClient.UseDefaultCredentials = False
mailClient.Credentials = basicAuthenticationInfo
mailClient.Send(Email)

%>

update

not able to telnet smtp server from the vps, but from local systems its possible.

You may need to add your outgoing IP address of your IIS server to your firewall. Go to http://whatismyipaddress.com/ if you're able to, this will tell you your outbound address.
You may need to look at your antivirus configuration - if you're using McAffee this may help: http://digital.ni.com/public.nsf/allkb/76D1CFA7F3C047D08625719B006861B5
instead of specifying "host" in your code as the SMTP server hostname, you could try specifying the IP address of your SMTP server
also once you can telnet to the SMTP server, make sure there's no anti-spam getting in the way that is stopping your application from finally connecting to the actual SMTP server