Integration Services :: Unable To Connect To A Webpage From SSIS

I am trying to connect to a Web page from SSIS and I've tried both http connection manager and a Script Task but none of them seems to be working.

I get the following errors:

Through Script Component: Exception has been thrown by the target of an invocation.

Through http connection manager: The remote server returned an error: (503) Server Unavailable.

Here is one of the VB code I've tried:

Public Sub Main()
Dim MyWebClient As New System.Net.WebClient()
Dim proxyObject As New System.Net.WebProxy("BANANA:8080", True)
MyWebClient.Proxy = proxyObject

[Code] ....

And, here is one of the C# codes I've tried:

public void Main()
{
Variables varCollection = null;
Dts.VariableDispenser.LockForRead("User::RemoteUri");
Dts.VariableDispenser.LockForRead("User::LocalFolder");
Dts.VariableDispenser.GetVariables(ref varCollection);
varCollection.Unlock();

[Code] ...

I could open the same web page mentioned in the code manually in all my browsers (IE, Firefox, Chrome).

I am using SQL Server 2014.