Troubleshoot network-related errors when you install or use Visual Studio

We've got solutions for the most typical network- or proxy-related errors that you might encounter when you install or use Visual Studio behind a firewall or a proxy server.

Error: “Proxy authorization required”

This error generally occurs when users are connected to the internet through a proxy server, and the proxy server blocks the calls that Visual Studio makes to some network resources.

To fix this proxy error

  • Restart Visual Studio. A proxy authentication dialog box should appear. Enter your credentials when prompted in the dialog.

  • If restarting Visual Studio does not solve the problem, it might be that your proxy server does not prompt for credentials for http://go.microsoft.com addresses but does so for *.visualStudio.microsoft.com addresses. For these servers, consider adding the following URLs to an allow list to unblock all sign-in scenarios in Visual Studio:

    • *.windows.net

    • *.microsoftonline.com

    • *.visualstudio.microsoft.com

    • *.microsoft.com

    • *.live.com

  • You can otherwise remove the http://go.microsoft.com address from the allow list so that the proxy authentication dialog shows up for both the http://go.microsoft.com address and the server endpoints when Visual Studio is restarted.

    -OR-

  • If you want to use your default credentials with your proxy, you can perform the following actions:

  1. Find devenv.exe.config (the devenv.exe configuration file) in: %ProgramFiles%\Microsoft Visual Studio\2017\Enterprise\Common7\IDE or %ProgramFiles(x86)%\Microsoft Visual Studio\2017\Enterprise\Common7\IDE.

  2. In the configuration file, find the <system.net> block, and then add this code:

    <defaultProxy enabled="true" useDefaultCredentials="true">
        <proxy bypassonlocal="True" proxyaddress="http://<yourproxy:port#>"/>
    </defaultProxy>
    

    You must insert the correct proxy address for your network in proxyaddress="<http://<yourproxy:port#>.

  1. Find devenv.exe.config (the devenv.exe configuration file) in: %ProgramFiles%\Microsoft Visual Studio\2019\Enterprise\Common7\IDE or %ProgramFiles(x86)%\Microsoft Visual Studio\2019\Enterprise\Common7\IDE.

  2. In the configuration file, find the <system.net> block, and then add this code:

    <defaultProxy enabled="true" useDefaultCredentials="true">
        <proxy bypassonlocal="True" proxyaddress="http://<yourproxy:port#>"/>
    </defaultProxy>
    

    You must insert the correct proxy address for your network in proxyaddress="<http://<yourproxy:port#>.

Error: “Disconnected from Visual Studio” when attempting to report a problem

This error generally occurs when a user is connected to the internet through a proxy server, and the proxy server blocks the calls that Visual Studio makes to some network resources.

To fix this proxy error

  1. Find feedback.exe.config (the feedback.exe configuration file) in: %ProgramFiles(x86)%\Microsoft Visual Studio\Installer or %ProgramFiles%\Microsoft Visual Studio\Installer.

  2. In the configuration file, check whether the following code is present; if the code isn't present, add it before the last </configuration> line.

    <system.net>
        <defaultProxy useDefaultCredentials="true" />
    </system.net>
    

Error: “The underlying connection was closed”

If you are using Visual Studio in a private network that has a firewall, Visual Studio might not be able to connect to some network resources. These resources can include Azure DevOps Services for sign-in and licensing, NuGet, and Azure services. If Visual Studio fails to connect to one of these resources, you might see the following error message:

The underlying connection was closed: An unexpected error occurred on send

Visual Studio uses Transport Layer Security (TLS) 1.2 protocol to connect to network resources. Security appliances on some private networks block certain server connections when Visual Studio uses TLS 1.2.

To fix this connection error

Enable connections for the following URLs:

  • https://management.core.windows.net

  • https://app.vssps.visualstudio.com

  • https://login.microsoftonline.com

  • https://login.live.com

  • https://go.microsoft.com

  • https://graph.windows.net

  • https://app.vsspsext.visualstudio.com

  • *.azurewebsites.net (for Azure connections)

  • *.visualstudio.microsoft.com

  • cdn.vsassets.io (hosts content delivery network, or CDN, content)

  • *.gallerycdn.vsassets.io (hosts Azure DevOps Services extensions)

  • static2.sharepointonline.com (hosts resources that Visual Studio uses in the Office UI Fabric kit, such as fonts)

  • *.nuget.org (for NuGet connections)

    Note

    Privately owned NuGet server URLs may not be included in this list. You can check for the NuGet servers that you are using in %APPData%\Nuget\NuGet.Config.

Error: "Failed to parse ID from parent process"

You might encounter this error message when you use a Visual Studio bootstrapper and a response.json file on a network drive. The error's source is the User Account Control (UAC) in Windows.

Here's why this error can happen: A mapped network drive or UNC share is linked to a user's access token. When UAC is enabled, two user access tokens are created: One with administrator access, and one without administrator access. When a network drive or share is created, the user's current access token is linked to it. Because the bootstrapper must be run as administrator, it won't be able to access the network drive or share if either the drive or the share isn't linked to a user access token that has administrator access.

To fix this error

You can use the net use command or you can change the UAC Group Policy setting. For more information about these workarounds and how to implement them, see the following Microsoft support articles:

Get support

Sometimes, things can go wrong. If your Visual Studio installation fails, see Troubleshoot Visual Studio installation and upgrade issues for step-by-step guidance.

Here are a few more support options:

  • We also offer an installation chat (English only) support option for installation-related issues.
  • Report product issues to us via the Report a Problem tool that appears both in the Visual Studio Installer and in the Visual Studio IDE. If you're an IT Administrator and don't have Visual Studio installed, you can submit IT Admin feedback here.
  • Suggest a feature, track product issues, and find answers in the Visual Studio Developer Community.

See also