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

Applies to: Visual Studio Visual Studio for Mac

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

Error: “Proxy authorization required”

This error generally occurs when users connect to the internet through a proxy server. The proxy server then blocks the calls that Visual Studio makes to some network resources.

To fix this proxy error

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

• If restarting Visual Studio doesn't solve the problem, it might be because your proxy server doesn't prompt for credentials for http://go.microsoft.com addresses, but it does so for *.visualStudio.microsoft.com addresses. For these servers, add the following URLs to an allowlist to unblock all sign-in scenarios in Visual Studio:

  • *.windows.net

  • *.microsoftonline.com

  • *.visualstudio.microsoft.com

  • *.microsoft.com

  • *.live.com

• We recommend that you remove the http://go.microsoft.com address from the allowlist. Removing the address allows the proxy authentication dialog to show up for both the http://go.microsoft.com address and the server endpoints when Visual Studio restarts.

  -OR-

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

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

This error generally occurs when a user connects to the internet through a proxy server. The proxy server then 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're 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:

• Mapped drives aren't available from an elevated prompt when UAC is configured to "Prompt for credentials" in Windows
• Programs may be unable to access some network locations after you turn on User Account Control in Windows operating systems

Support or troubleshooting

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

• Install and use Visual Studio behind a firewall or proxy server
• Visual Studio administrator guide
• Install Visual Studio