Microsoft Knowledge Base Email Alertz

KBAlertz.com: If you send a Web request to the localhost through a proxy that is also running on the localhost, the request does not succeed.

Receive Microsoft Knowledge Base articles by E-Mail?

Every night we scan the Microsoft Knowledge Base. If technologies you're interested in are updated, we'll send you an e-mail. You only get one e-mail a day, and only when new articles are added.

Click here to create a
FREE account
Already have an account?
[Click here to Login]

Search KbAlertz

Advanced Search

Webmasters
Put kbAlertz on your website.
[ Click Here for more! ]





ASP.NET 3.5 Web Hosting with Windows 2008 and SQL 2008: Click Here!
Discount ASP.NET Hosting
ASP.NET 2.0 and 3.5
Windows2008 and SQL2008
US and UK Hosting
KBAlertz referrals get
** SIX MONTHS FREE **


Community Site



We Send hundreds of thousands of emails using ASP.NET Email


ASP.NET 3.5 Web Hosting with Windows 2008 and SQL 2008: Click Here!
Discount ASP.NET Hosting
ASP.NET 2.0 and 3.5
Windows2008 and SQL2008
US and UK Hosting
KBAlertz referrals get
** SIX MONTHS FREE **




Mentioned In








Microsoft Knowledge Base Article

This article contents is Microsoft Copyrighted material.
©2005-©2007 Microsoft Corporation. All rights reserved. Terms of Use | Trademarks




Article ID: 317718 - Last Review: February 12, 2007 - Revision: 2.2

BUG: You Cannot Connect to a Proxy on Localhost When You Make a Web Request by Using a Loopback Address

This article was previously published under Q317718

On This Page

SYMPTOMS

If you send a Web request to the localhost through a proxy that is also running on the localhost, the request does not succeed.

CAUSE

This problem occurs because the proxy settings are always ignored for requests that are made to loopback addresses. The special case of proxy also running on the same loopback is not checked (such as the scenario in the "Symptoms" section).

RESOLUTION

To work around this problem, use the host name instead of loopback adapter name (for example, instead of "localhost" or instead of address 127.0.0.1).

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

Steps to Reproduce the Problem

Use the following code to reproduce this problem:
      WebProxy p = new WebProxy("localhost:8080", false);
      HttpWebRequest r = WebRequest.Create("http://localhost") as
      HttpWebRequest;
      r.Proxy = p;
      
      HttpWebResponse w = r.GetResponse() as HttpWebResponse;
				
This request for a loopback address is not routed through a proxy that is running on the same loopback adapter.

Additionally, you cannot use Network Monitor (Netmon) to capture traffic sent or received to or from localhost. You have to have the client and the server running on different physical computers for Netmon to capture traffic.

APPLIES TO
  • Microsoft .NET Framework Class Libraries 1.0
  • Microsoft .NET Framework Class Libraries 1.1
Keywords: 
kbbug kbfix KB317718
Retired KB ArticleRetired KB Content Disclaimer
This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
       

Community Feedback System

Very often, it takes hours to solve a problem. Very often, you've looked high and low, and have tried a lot of solutions. When you finally found it, chances are, it was because someone else helped you. Here's your chance to give back. Use our community feedback tool to let others know what worked for you and what didn't.

Please also understand that the community feedback system is not warranted to be correct, it's simply a system that we've built to let people try and help each other. If something in a feedback response doesn't make sense to you, or you're not comfortable making changes that the feedback talks about (like registry edits), please consult a professional.

Thank you for using kbAlertz.com Feedback System.

-- Scott Cate

Be the first to leave feedback, to help others about this knowledge base article.

(Optional) Name

(Optional) Public URL Or Email

Comments
No HTML -- Text Only Please