1. Jun 16, 2020  If that’s the cause of the ECONNREFUSED – connection refused by server error, simply disable the firewall and anti-virus software on your computer.
2. Follow these steps to troubleshoot why you receive the connection refused message. First, try accessing the problematic website on different browsers including Safari, Internet Explorer, or Firefox and confirm the site does not load still.
3. Mar 31, 2020  Hi Shais, I write about GNS3 VM connection problem. Icon GNs3 VM is grey instead icon local server is green. I’ve installed on my system Lenovo Windows 10 Pro, GNS3 2.1.12 and on the Vmware Workstation 15 GNS3 VM 0.10.14. GNS3 VM turn on proprely the Workstation Player when I open GNS3 as Administrator privilege. Firewall is turned off.
4. May 01, 2020  Ensure that local firewalls (e.g. Windows Firewall) or active antivirus programs are not interfering with your connection or blocking the filezilla.exe application. What can fix the ECONNREFUSED – Connection refused by server is disabling the firewall and anti-virus software on your computer. Here’s how to apply this fix on Windows: 1.
5. Expected behavior Actual behavior Information. Diagnostic ID: C66DCF4E-ED06-4A88-83D6-0921B7A7582C Docker for Mac: 1.12.0-beta21 (Build 10868) macOS: Version 10.11.5 (Build 15F34).
6. Remote connection error: ERRCONNECTIONREFUSED. Hello all, Knocking my head against a brick wall with this one. I've just installed Radarr on my HTCP to replace couchpotato yaay. I've forwarded the port I want to use in my router, and changed the port in Radarr to reflect that same port right after I installed it.

• Connection Refused For 1 In Macos 4
• Connection Refused For 1 In Macos 8

Telnet: connect to address 127.0.0.1: Connection refused on MacOS. CFSocket created in Swift not listening. Docker - Ubuntu - Nginx - MariaDB - Connection refused. Hot Network Questions How many weekdays from a Saturday Is starting an AWS instance with only ssh to port 22 significantly insecure?

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By Rick Anderson

This document shows how to:

• Require HTTPS for all requests.
• Redirect all HTTP requests to HTTPS.

No API can prevent a client from sending sensitive data on the first request.

Warning

API projects

Do not use RequireHttpsAttribute on Web APIs that receive sensitive information. RequireHttpsAttribute uses HTTP status codes to redirect browsers from HTTP to HTTPS. API clients may not understand or obey redirects from HTTP to HTTPS. Such clients may send information over HTTP. Web APIs should either:

Connection Refused For 1 In Macos 4

• Not listen on HTTP.
• Close the connection with status code 400 (Bad Request) and not serve the request.

HSTS and API projects

Connection Refused For 1 In Macos 8

The default API projects don't include HSTS because HSTS is generally a browser only instruction. Other callers, such as phone or desktop apps, do not obey the instruction. Even within browsers, a single authenticated call to an API over HTTP has risks on insecure networks. The secure approach is to configure API projects to only listen to and respond over HTTPS.

Warning

API projects

Do not use RequireHttpsAttribute on Web APIs that receive sensitive information. RequireHttpsAttribute uses HTTP status codes to redirect browsers from HTTP to HTTPS. API clients may not understand or obey redirects from HTTP to HTTPS. Such clients may send information over HTTP. Web APIs should either:

• Not listen on HTTP.
• Close the connection with status code 400 (Bad Request) and not serve the request.

Require HTTPS

We recommend that production ASP.NET Core web apps use:

• HTTPS Redirection Middleware (UseHttpsRedirection) to redirect HTTP requests to HTTPS.
• HSTS Middleware (UseHsts) to send HTTP Strict Transport Security Protocol (HSTS) headers to clients.

Note

Apps deployed in a reverse proxy configuration allow the proxy to handle connection security (HTTPS). If the proxy also handles HTTPS redirection, there's no need to use HTTPS Redirection Middleware. If the proxy server also handles writing HSTS headers (for example, native HSTS support in IIS 10.0 (1709) or later), HSTS Middleware isn't required by the app. For more information, see Opt-out of HTTPS/HSTS on project creation.

UseHttpsRedirection

The following code calls UseHttpsRedirection in the Startup class:

The preceding highlighted code:

• Uses the default HttpsRedirectionOptions.RedirectStatusCode (Status307TemporaryRedirect).
• Uses the default HttpsRedirectionOptions.HttpsPort (null) unless overridden by the ASPNETCORE_HTTPS_PORT environment variable or IServerAddressesFeature.

We recommend using temporary redirects rather than permanent redirects. Link caching can cause unstable behavior in development environments. If you prefer to send a permanent redirect status code when the app is in a non-Development environment, see the Configure permanent redirects in production section. We recommend using HSTS to signal to clients that only secure resource requests should be sent to the app (only in production).

Port configuration

A port must be available for the middleware to redirect an insecure request to HTTPS. If no port is available:

• Redirection to HTTPS doesn't occur.
• The middleware logs the warning 'Failed to determine the https port for redirect.'

Specify the HTTPS port using any of the following approaches:

• Set HttpsRedirectionOptions.HttpsPort.

• Set the https_porthost setting:

  • In host configuration.

  • By setting the ASPNETCORE_HTTPS_PORT environment variable.

  • By adding a top-level entry in appsettings.json:

• Indicate a port with the secure scheme using the ASPNETCORE_URLS environment variable. The environment variable configures the server. The middleware indirectly discovers the HTTPS port via IServerAddressesFeature. This approach doesn't work in reverse proxy deployments.

• Set the https_porthost setting:

  • In host configuration.

  • By setting the ASPNETCORE_HTTPS_PORT environment variable.

  • By adding a top-level entry in appsettings.json:

• Indicate a port with the secure scheme using the ASPNETCORE_URLS environment variable. The environment variable configures the server. The middleware indirectly discovers the HTTPS port via IServerAddressesFeature. This approach doesn't work in reverse proxy deployments.

• In development, set an HTTPS URL in launchsettings.json. Enable HTTPS when IIS Express is used.

• Configure an HTTPS URL endpoint for a public-facing edge deployment of Kestrel server or HTTP.sys server. Only one HTTPS port is used by the app. The middleware discovers the port via IServerAddressesFeature.

Note

When an app is run in a reverse proxy configuration, IServerAddressesFeature isn't available. Set the port using one of the other approaches described in this section.

Edge deployments

When Kestrel or HTTP.sys is used as a public-facing edge server, Kestrel or HTTP.sys must be configured to listen on both:

• The secure port where the client is redirected (typically, 443 in production and 5001 in development).
• The insecure port (typically, 80 in production and 5000 in development).

The insecure port must be accessible by the client in order for the app to receive an insecure request and redirect the client to the secure port.

For more information, see Kestrel endpoint configuration or HTTP.sys web server implementation in ASP.NET Core.

Deployment scenarios

Any firewall between the client and server must also have communication ports open for traffic.

If requests are forwarded in a reverse proxy configuration, use Forwarded Headers Middleware before calling HTTPS Redirection Middleware. Forwarded Headers Middleware updates the Request.Scheme, using the X-Forwarded-Proto header. The middleware permits redirect URIs and other security policies to work correctly. When Forwarded Headers Middleware isn't used, the backend app might not receive the correct scheme and end up in a redirect loop. A common end user error message is that too many redirects have occurred.

When deploying to Azure App Service, follow the guidance in Tutorial: Bind an existing custom SSL certificate to Azure Web Apps.

Options

The following highlighted code calls AddHttpsRedirection to configure middleware options:

Calling AddHttpsRedirection is only necessary to change the values of HttpsPort or RedirectStatusCode.

The preceding highlighted code:

• Sets HttpsRedirectionOptions.RedirectStatusCode to Status307TemporaryRedirect, which is the default value. Use the fields of the StatusCodes class for assignments to RedirectStatusCode.
• Sets the HTTPS port to 5001.

Configure permanent redirects in production

The middleware defaults to sending a Status307TemporaryRedirect with all redirects. If you prefer to send a permanent redirect status code when the app is in a non-Development environment, wrap the middleware options configuration in a conditional check for a non-Development environment.

When configuring services in Startup.cs:

HTTPS Redirection Middleware alternative approach

An alternative to using HTTPS Redirection Middleware (UseHttpsRedirection) is to use URL Rewriting Middleware (AddRedirectToHttps). AddRedirectToHttps can also set the status code and port when the redirect is executed. For more information, see URL Rewriting Middleware.

When redirecting to HTTPS without the requirement for additional redirect rules, we recommend using HTTPS Redirection Middleware (UseHttpsRedirection) described in this topic.

HTTP Strict Transport Security Protocol (HSTS)

Per OWASP, HTTP Strict Transport Security (HSTS) is an opt-in security enhancement that's specified by a web app through the use of a response header. When a browser that supports HSTS receives this header:

• The browser stores configuration for the domain that prevents sending any communication over HTTP. The browser forces all communication over HTTPS.
• The browser prevents the user from using untrusted or invalid certificates. The browser disables prompts that allow a user to temporarily trust such a certificate.

Because HSTS is enforced by the client, it has some limitations:

• The client must support HSTS.
• HSTS requires at least one successful HTTPS request to establish the HSTS policy.
• The application must check every HTTP request and redirect or reject the HTTP request.

ASP.NET Core 2.1 and later implements HSTS with the UseHsts extension method. The following code calls UseHsts when the app isn't in development mode:

UseHsts isn't recommended in development because the HSTS settings are highly cacheable by browsers. By default, UseHsts excludes the local loopback address.

For production environments that are implementing HTTPS for the first time, set the initial HstsOptions.MaxAge to a small value using one of the TimeSpan methods. Set the value from hours to no more than a single day in case you need to revert the HTTPS infrastructure to HTTP. After you're confident in the sustainability of the HTTPS configuration, increase the HSTS max-age value; a commonly used value is one year.

The following code:

• Sets the preload parameter of the Strict-Transport-Security header. Preload isn't part of the RFC HSTS specification, but is supported by web browsers to preload HSTS sites on fresh install. For more information, see https://hstspreload.org/.
• Enables includeSubDomain, which applies the HSTS policy to Host subdomains.
• Explicitly sets the max-age parameter of the Strict-Transport-Security header to 60 days. If not set, defaults to 30 days. For more information, see the max-age directive.
• Adds example.com to the list of hosts to exclude.

UseHsts excludes the following loopback hosts:

• localhost : The IPv4 loopback address.
• 127.0.0.1 : The IPv4 loopback address.
• [::1] : The IPv6 loopback address.

Opt-out of HTTPS/HSTS on project creation

In some backend service scenarios where connection security is handled at the public-facing edge of the network, configuring connection security at each node isn't required. Web apps that are generated from the templates in Visual Studio or from the dotnet new command enable HTTPS redirection and HSTS. For deployments that don't require these scenarios, you can opt-out of HTTPS/HSTS when the app is created from the template.

To opt-out of HTTPS/HSTS:

Uncheck the Configure for HTTPS check box.

Use the --no-https option. For example

Trust the ASP.NET Core HTTPS development certificate on Windows and macOS

The .NET Core SDK includes an HTTPS development certificate. The certificate is installed as part of the first-run experience. For example, dotnet --info produces a variation of the following output:

Installing the .NET Core SDK installs the ASP.NET Core HTTPS development certificate to the local user certificate store. The certificate has been installed, but it's not trusted. To trust the certificate, perform the one-time step to run the dotnet dev-certs tool:

The following command provides help on the dev-certs tool:

How to set up a developer certificate for Docker

See this GitHub issue.

Trust HTTPS certificate from Windows Subsystem for Linux

The Windows Subsystem for Linux (WSL) generates an HTTPS self-signed cert. To configure the Windows certificate store to trust the WSL certificate:

• Run the following command to export the WSL-generated certificate:

• In a WSL window, run the following command:

  The preceding command sets the environment variables so Linux uses the Windows trusted certificate.

Troubleshoot certificate problems

This section provides help when the ASP.NET Core HTTPS development certificate has been installed and trusted, but you still have browser warnings that the certificate is not trusted. The ASP.NET Core HTTPS development certificate is used by Kestrel.

All platforms - certificate not trusted

Run the following commands:

Close any browser instances open. Open a new browser window to app. Certificate trust is cached by browsers.

The preceding commands solve most browser trust issues. If the browser is still not trusting the certificate, follow the platform-specific suggestions that follow.

Docker - certificate not trusted

• Delete the C:Users{USER}AppDataRoamingASP.NETHttps folder.
• Clean the solution. Delete the bin and obj folders.
• Restart the development tool. For example, Visual Studio, Visual Studio Code, or Visual Studio for Mac.

Windows - certificate not trusted

• Check the certificates in the certificate store. There should be a localhost certificate with the ASP.NET Core HTTPS development certificate friendly name both under Current User > Personal > Certificates and Current User > Trusted root certification authorities > Certificates
• Remove all the found certificates from both Personal and Trusted root certification authorities. Do not remove the IIS Express localhost certificate.
• Run the following commands:

Close any browser instances open. Open a new browser window to app.

OS X - certificate not trusted

• Open KeyChain Access.
• Select the System keychain.
• Check for the presence of a localhost certificate.
• Check that it contains a + symbol on the icon to indicate it's trusted for all users.
• Remove the certificate from the system keychain.
• Run the following commands:

Close any browser instances open. Open a new browser window to app.

See HTTPS Error using IIS Express (dotnet/AspNetCore #16892) for troubleshooting certificate issues with Visual Studio.

IIS Express SSL certificate used with Visual Studio

To fix problems with the IIS Express certificate, select Repair from the Visual Studio installer. For more information, see this GitHub issue.

Additional information

Connection errors are equally annoying for visitors and website operators. However, very few of these error messages are caused by the website itself. Usually, the problem lies on the visitor’s end and they can correct it themselves. However, the situation can quickly become frustrating if you try to fix it without any information. One of the most persistent errors is the message “ERR_CONNECTION_REFUSED”, which should be well known to most Chrome users. If the 102 error appears in Google’s browser, it is usually not enough to reload the page or access it again at a later time.

1. How to fix the ERR_CONNECTION_REFUSED error message

What is behind the ERR_CONNECTION_REFUSED Chrome error?

When you visit a website with Google Chrome and receive the error message ERR_CONNECTION_REFUSED, it means that your attempt to connect with the page was refused. While the error message with the error code 102 only appears in this form on Google Chrome, the problem itself also occurs on other browsers like Firefox if a connection to the target website is unavailable or impossible. The ERR_CONNECTION_REFUSED error is a client-side problem that can be caused by incorrect firewall, system or browser settings, but also by malware or a faulty Internet connection. In exceptional cases, however, the message is also displayed if the website is unavailable (however, other messages are provided for this by default).

The connection error does not necessarily affect website visitors, as the following example shows: if web developers work with Google Chrome and temporary local addresses for individual resources of a website, these addresses are often inaccessible when their URLs end on .localhost. The ERR_CONNECTION_REFUSED message in this case is due to a security feature introduced on Chrome version 43 that automatically blocks these localhost subdomains.

A rejected connection message may appear regardless of the operating system used. You can therefore encounter an ERR_CONNECTION_REFUSED error message on Windows 10, as well as on a Mac. Android users can also be confronted with the connection problem if they use Chrome.

How to fix the ERR_CONNECTION_REFUSED error message

The fact that the ERR_CONNECTION_REFUSED error message appears almost always due to a client-side misconfiguration or a technical problem on the user’s side means that you have the chance to fix the problem on your own. However, the difficulty is that there are many potential causes of errors that can be responsible for blocking the connection. However, the browser message does not indicate what prevented the desired page from being accessed in the specific case. Therefore, you have no other choice than to try out the various solutions one by one until the error is corrected and the website can be accessed again as usual.

Which methods for correcting the ERR_CONNECTION_REFUSED error message are most likely to succeed?

Solution 1: Check the website status

Before looking for a solution to your internet connection and the internet or browser settings, you should rule out that the ERR_CONNECTION_REFUSED error is caused by the contacted web server. Even if the likelihood of this is minimal, you should first check if the website is just offline and the Chrome 102 error is displayed instead of the usual messages like a HTTP 503 message.

In principle, you have two options for checking the status of the website: the classic way is to try and access other sites. If these can be loaded without the ERR_CONNECTION_REFUSED error message, this is a clear sign of a server-side problem on the actual target page. A second option is to use the web tool Down For Everyone Or Just Me?. Enter the web address of the non-functioning webpage and start a quick check by clicking on “or just me?” to check the general functionality of this page. After a few seconds, you will receive a result: the website is offline (“down”) or online (“up”).

Solution 2: Restart the router

One of the most common solutions to various errors on the internet is to restart the network device that connects you to the internet. Although the chance of success is rather low in most cases, you should also try this when this ERR_CONNECTION_REFUSED error message appears – especially since restarting the router is a matter of a few minutes. Just disconnect the power supply by unplugging the router’s power supply and wait about 30 seconds before reconnect with the plug. When the router boots up again, try to access the target website again with your browser. If the connection problem persists, there must be another cause.

Solution 3: Clear Browser Cache

Like all internet browsers, Chrome stores a lot of information in the program’s cache. These include the history of visited websites, cookies, or static content like images or log-in data, which are recorded in the cache in order to be able to load the corresponding pages more quickly the next time they are accessed. However, this can become a problem if these cache states are outdated and therefore no longer match the current version of the contacted website. A possible solution to fix the ERR_CONNECTION_REFUSED error message in Chrome is to clear the Google Chrome’s browser cache.

The menu needed to achieve this can be accessed in two ways:

1. Click on the three-point symbol in the browser’s menu bar and then select “more tools” and click on “delete browser data”.
2. Access the address chrome://settings/clearBrowserData on the Chrome address line.

In both cases, you can go directly to the browser cache menu, where you can remove the cache files with a single click on the “DELETE DATA” button. Please make sure that all listed file categories, as well as the option “total time” (under “period”) are selected, otherwise Chrome will not empty the entire cache, just certain files and the cache from the last couple of hours or days.

Solution 4: Check proxy settings and adjust them if necessary

The protection of privacy on the internet has been an important issue for browser manufacturers and users for years. However, the increasingly important role security features have played in the development of websites does not prevent many users from using individual solutions to protect their own data. Particularly popular is the use of proxy servers, which act as an intermediary between the browser and websites. In this way, they can filter communication and cache data, as well as keep the IP address of the user secret from the contacted web server.

However, there are various scenarios in which a proxy server can cause problems like the ERR_CONNECTION_REFUSED error message. For example, the web server could block the proxy or its IP address and therefore reject the connection. Another possible source of errors is the caching function of the proxy servers – as soon as the cache contains obsolete data, connection errors cannot be excluded. Of course, it is also possible that the proxy is offline or incorrectly configured, which would also cause the connection to fail.

If you receive a message like the Chrome 102 error, it is recommended to check your own proxy settings and delete registered servers in case of doubt. For this purpose, Chrome even has its own entry in the browser options, which saves you having to search for the corresponding menu in your system settings. In the first step, open the Chromes settings by entering the following address in the search bar:

Click on “advanced” to open the complete menu. Under “system”, you will find the entry “open proxy settings”, which takes you to the corresponding menu on your operating system.

Windows users then click on “LAN settings” and uncheck (if necessary) “use proxy server for LAN”. Mac users immediately land in the appropriate menu and only have to uncheck all selectable proxy protocols.

Solution 5: Temporarily disable firewall and antivirus software

Firewalls and programs against malware and the like also serve to protect users and systems. To this end, they filter network traffic and scan the system at regular intervals to automatically block malicious and conspicuous (potentially unsafe) pages or detect known malware. However, as important as this security software is, it is also problematic if it unjustly blocks pages or content and therefore prevents connections from being established.

In order to protect your privacy, the video will not load until you click on it.

A solution to the ERR_CONNECTION_REFUSED error message is therefore to temporarily deactivate the firewall and the like. If the project can then be called up, you know the cause of the connection problem and can make corresponding changes to the programs filter lists. Alternatively, you can switch to other security tools.

Solution 6: Clear DNS cache (DNS flush)

While most people are probably aware of the browser cache, only a few internet users know that the operating system also collects information about browsing habits. For example, the DNS cache contains temporary entries for all pages that you have called up with your browser. In detail, these entries contain all the information required for the name resolution of the respective domain addresses, which means that the DNS cache performs a similar task as the browser cache (acceleration of the loading process). This caching eliminates the need to contact a DNS server again, saving a lot of time.

However, the fact that the query is answered directly from the cache is not always an advantage. If an entry no longer matches the current version of the website, technical problems and connection errors like the ERR_CONNECTION_REFUSED error message are not unusual. The simple and quick solution is to clear the DNS cache, which you can easily do from your systems command line. With Windows, the command required for this is as follows:

You can find out what the corresponding commands for macOS and Linux look like in our guide – including more information about the DNS cache and DNS flush.

Solution 7: Change DNS server

Name resolution is one of the basic building blocks of computer network functionality. This means that an outdated DNS entry is not the only potential source of errors like the ERR_CONNECTION_REFUSED error message on Android and iOS that originates from the Domain Name System. The DNS server itself can also be responsible for these kinds of connection errors if it does not function properly, for example, because it is overloaded or even offline.

In most cases, the DNS server address is automatically obtained from the internet provider, although selected name server can easily be entered for name resolution. The Google servers (8.8.8.8 and 8.8.4.4) and the CDN provider Cloudflare (1.1.1.1 and 1.0.0.1) are particularly recommended.

Solution 8: Disable Chrome extensions

Extensions broaden the functionality of your Chrome installation, but the majority of these are not from Google, instead they have been developed by third parties. If you use extensions, you have no guarantee that they will work as intended, and will be updated regularly (to be compatible with the current Chrome version). Since incorrect or obsolete extensions can also cause error messages like ERR_CONNECTION_REFUSED, you should always consider a thorough check of the chrome add-ons you have installed. First, open the “extensions” menu by accessing the following address:

The individual extensions can now be deactivated by moving the slider to the left:

If the target website can be executed correctly after you have switched off all extensions, you know that at least one extension is responsible for the ERR_CONNECTION_REFUSED error message. Activate the extensions one after the other to find the culprit(s) and then delete them using the “REMOVE” button.

Solution 9: Reinstalling Chrome

Like any other application, Chrome is not bug-free. Many errors can be quickly corrected thanks to regular updates, but problemsbetween the browser and the operating system can still occur, which cannot be solved despite updates. If this even results in connection errors like the 102 error, you will usually just have to completely reinstall Chrome completely. You can delete the current installation from your software center and download the required file for a new installation from the official Chrome Website.

Solution 10: Contact provider

While you can change DNS servers on your own and therefore replace the standard solution of your internet provider, you have no influence whatsoever on the packet filtering performed by your provider. Since there is at least the possibility that this blocks the website you are targeting through the provider’s own firewall system, you should not hesitate to contact support if these DIY solutions are not successful. If you are lucky, the page in question is actually blocked, so it is sufficient to order an unblocking to correct the ERR_CONNECTION_REFUSED error.

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