ERR_CONNECTION_CLOSED: How to fix the connection error

Before you delve deeply into the configuration of the system and browser to find the source of the "ERR_CONNECTION_CLOSED" error and fix it, first check your internet connection. With Windows, for example, you can do this via the network symbol in the notification area (also called the System Tray). There you can see not only the network to which you are currently connected, but also the connection status.

Connection problems that lead to errors such as the "ERR_CONNECTION_CLOSED" message may also be due to errors in the system's TCP/IP setup. However, you can solve this problem by resetting the settings for the TCP/IP stack to their original state. All you need is administrator rights and the command line tool Netshell (netsh), which has been installed by default since Windows 2000. To start the command prompt as an administrator, first access the Start menu (Windows icon) and enter the term "cmd" in the search bar. Then right-click on the cmd application presented as a search result and select "Run as administrator":

Proxies and VPN connections offer you - each in their own way - the possibility of remaining anonymous during your time on the internet. Both solutions are actively involved in the data transfer process, which is why they can also cause complications and, for example, cause the "ERR_CONNECTION_RESET" error. If you use one of the two bridging techniques, you should deactivate it - at least for testing purposes - or - in the case of VPN - not use it. To deactivate the proxy server, you need the "Internet settings" menu, which can be accessed via the control panel:

Then switch to the "Connections" tab. In the upper window you will find a list of configured VPN and dial-up connections. If you have set up a VPN connection, you can also simply delete it here using the "Remove" button:

The configuration of the proxy settings works via the "LAN settings" option, which can be found in the lower part of the window:

This will open the DNS settings in the hidden options menu "Net Internals". In addition to a list of valid and expired DNS entries, here you will find the "Clear host cache" button, which can be used to clear the cache.

It’s not only the cache of the used DNS server that can become a problem: If the availability of the server is limited or the server is completely down, the connection may also be interrupted and the Chrome error message may appear. Usually you obtain the address of the DNS server automatically, so that you are assigned a local nameserver from your internet provider. However, you have the option of entering the server manually and thus transferring the name resolution task to another server in order to fix the "ERR_CONNECTION_CLOSED" message. To do this, proceed as follows:

Open the overview of active network connections, for example via the Network and Sharing Center or the key combination [Windows key] +[R] followed by the entry "ncpa.cpl".

Right-click on the network connection via which you are connected to the internet and click on "Properties" in the pop-up menu (requires administrator rights). Search for the entry "Internet Protocol Version 4 (TCP/IPv4)" and open the protocol’s configuration menu by double clicking. Leave the IP address settings unchanged (automatically or manually entered address) and select the option "Use the following DNS server addresses" in the lower area of the menu. Then enter the server addresses of your choice. For example, the addresses of Google servers (8.8.8.8.8 and 8.8.4.4) are recommended:

Even the best security setup does not offer 100% protection against malware. Therefore, you can never rule out that your system has been infected with malicious software and this is what’s causing the disconnections. For this purpose, Chrome offers its own solution for detecting and removing malware, which you can start directly in the browser settings. To do this, open the settings menu by clicking on the three-point symbol and selecting "Settings":

Select "Advanced" to expand the advanced options menu. Under "Reset and clean up" you will find the "Clean up computer" button, which leads you to the cleanup tool:

To start the tool, click on "SEARCH". If you don't want Chrome to collect information about detected malware as well as your system settings and processes, you need to move the slider to the left under "Report details to Google".

Extensions in Chrome are important building blocks for extending the functionality of the Google browser. There are thousands of free extensions available in the Chrome Store, which are extremely practical in principle, but also cause problems such as the "ERR_CONNECTION_CLOSED" error - especially if the extensions are no longer compatible with the current browser version. To check whether an installed extension is the cause of the error message, deactivate it temporarily. Simply enter the URL chrome://extensions in the address bar and move the sliders below each extension to the left:

Chrome then checks if the current version is installed and automatically starts the update process if you are using an outdated version. If your browser is up to date, you will see the message "Google Chrome is up to date":