Visual Studio Error: (407: Proxy Authentication Required)

The situation is essentially that VS is not set up to go through a proxy to get to the resources it's trying to get to (when using FTP). This is the cause of the 407 error you're getting. I did some research on this and there are a few things that you can try to get this debugged. Fundamentally this is a bit of a flawed area in the product that is supposed to be reviewed in a later release.

Here are some solutions, in order of less complex to more complex:

  • If possible don't use the proxy for the specified domains that you're trying to get to.

  • Set up your proxy settings correctly Internet Explorer (even if you don't use it) as that affects system wide settings. Even go so far as to connect to the internet with internet explorer and leave it connected then go back and try again from VS.

  • In the devenv.exe.config add <servicePointManager expect100Continue="false" /> as laid out below:
    • <configuration>
  <system.net>
    <settings>
      <servicePointManager expect100Continue="false" />
    </settings>
  </system.net>
</configuration>

  • Add defaultProxy settings as follows:
    • <system.net>
  <defaultProxy useDefaultCredentials="true" enabled="true">
      <proxy proxyaddress="http://your.proxyserver.ip:port"/>
  </defaultProxy>
  <settings>
  ...

  • Alternately you could try telling it to use system default (which should pull from internet explorer) like so: 
    <defaultProxy useDefaultCredentials="true" enabled="true">
    <proxy usesystemdefault="True" />
</defaultProxy>

  • There is an older solution involving creating a plugin here

    • Hope this solves it for you.


    After three days of searching, the solution fell into my lap.

    Now, what happened was VS tried to do an automatic update but was stopped by the proxy. I was prompted for credentials and the check took place.

    I was inspired to check the TFS server connection just for kicks in case that prompt would possibly establish a connection for the TFS server to tunnel through... lo and behold! It worked!

    WORKAROUND:

    1. Open TOOLS>Extensions & Updates
    2. Click on Updates... in the left-hand menu
    3. There will be a failure notice on screen and a link to enter your credentials. Click it and enter them.
    4. Close the Extension manager.
    5. Click TEAM>Connect to TFS server...
    6. Enter the address and it will work!

    Note: Some have suggested trying to use the proxy credential prompt by opening the integrated browser but this has not worked. I am not an expert but I think they are connecting through different channels within windows itself.

    There is no editing of devenv.exe.config required for this to work.

    It will be a pain to have to check for updates manually every time you need to connect to the server, but this is the best solution I have come up with until Microsoft fixes this issue permanently with an update or future release.


    While running Visual Studio 2012 behind a proxy, I received the following error message when checking for extension updates in the Visual Studio Gallery:

    The remote server returned an unexpected response: (417) Expectation failed

    A look around Google finally revealed a solution here:

    Visual Studio 2012 Proxy Settings

    http://www.jlpaonline.com/?p=176

    Basically, he's saying the fix is to edit your devenv.exe.config file and change this:

    <settings>      
   <ipv6 enabled="true"/> 
</settings>

    to this:

     <settings>
   <ipv6 enabled="true"/>      
   <servicePointManager expect100Continue="false"/> 
 </settings>

    Tags:

    Visual Studio

    Proxy

    Proxy Authentication

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