My project wont compile. I am receiveing this error

Warning 1: The referenced assembly "IntelliSMSDotNet" could not be resolved because it has a dependency on "System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" which is not in the currently targeted framework ".NETFramework,Version=v4.0,Profile=Client". Please remove references to assemblies not in the targeted framework or consider retargeting your project.

How do I go about resolving this

I have resolved the previous issue, but now I am faced by this error. Please advise.


************** Exception Text **************
IntelliSoftware.IntelliSMSException: HTTP Error occurred trying to connecting to the IntelliSoftware gateway, see InnerException for details ---> System.Net.WebException: The remote server returned an error: (407) Proxy Authentication Required.
at System.Net.HttpWebRequest.GetResponse()
at IntelliSoftware.Common.HTTPConnection.HTTPRequest(String sMethod, String sUrl, String sContentType, String sFormData)
at IntelliSoftware.Internal.SMSGatewayService.MakeHTTPRequest(String sURL, SMSGatewayRequestData objSMSGatewayRequestData, String sReturnCodePrefix, String& sRawResponse, ResultCodes& ResultCode, Exception& InternalException)
--- End of inner exception stack trace ---
at IntelliSoftware.Internal.SMSGatewayService.MakeGatewayRequest(String sURL, SMSGatewayRequestData objSMSGatewayRequestData, String sReturnCodePrefix, Boolean bSendLogParams, String& sRawResponse, ResultCodes& ResultCode)
at IntelliSoftware.Internal.SMSGatewayService.MakeServiceRequest(String sURL, SMSGatewayRequestData objSMSGatewayRequestData, String sReturnCodePrefix, Boolean bSendLogParams, String& sRawResponse, ResultCodes& ResultCode)
at IntelliSoftware.Internal.SMSGatewayProxy.SendMessage(String sUsername, String sPassword, String sTo, String sFrom, String sText, String sUserContext, Boolean bRequestDeliveryRpt, Int32 nMaxConCatMsgs, ResultCodes& ResultCode)
at IntelliSoftware.IntelliSMS.SendMsg(String To, String Message, String From)
at SMSapplication.Form1.button1_Click(Object sender, EventArgs e) in C:\Users\tariq.5.adib\Documents\Visual Studio 2010\Projects\SMSapplication\SMSapplication\Form1.cs:line 37
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.225 (RTMGDR.030319-2200)
CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/mscorlib.dll

---

SMSapplication
Assembly Version: 1.0.0.0
Win32 Version: 1.0.0.0
CodeBase: file:///C:/Users/tariq.5.adib/Documents/Visual%20Studio%202010/Projects/SMSapplication/SMSapplication/bin/Debug/SMSapplication.exe

---

System.Windows.Forms
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 built by: RTMRel
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll

---

System.Drawing
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 built by: RTMRel
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll

---

System
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 built by: RTMRel
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll

---

System.Configuration
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 (RTMRel.030319-0100)
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll

---

System.Xml
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 built by: RTMRel
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll

---

IntelliSMSDotNet
Assembly Version: 4.5.0.0
Win32 Version: 4.5.0.0
CodeBase: file:///C:/Users/tariq.5.adib/Documents/Visual%20Studio%202010/Projects/SMSapplication/SMSapplication/bin/Debug/IntelliSMSDotNet.DLL

---

System.Web
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.206 built by: RTMGDR
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_32/System.Web/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Web.dll

---

System.Core
Assembly Version: 4.0.0.0
Win32 Version: 4.0.30319.1 built by: RTMRel
CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------

If you are accessing our gateway from ASP.Net and your proxy server
requires authentication, then HTTP access may be blocked. This is
because the ASP.Net Worker Process is running as a local machine account
(e.g. ASPNET). To fix this issue you can try running the ASP.Net Worker
Process as your own personal domain account (please note this may
introduce security risks).

For more details please see:
http://support.microsoft.com/kb/895967