FIX: Unable to connect to authentication service in LoL

Tashreef Shareef
by Tashreef Shareef
Windows & Software Expert
0 Comments
Download PDF

  • The League of Legends unable to connect to authentication service error usually occur due to incorrect DNS configuration.
  • Continue reading the article to troubleshoot the error on your Windows PC.
  • Do check out our dedicated Gaming Hub for more game-related articles.
  • Also, don't hesitate to explore the Troubleshooting section to fix issues with your system.
Fix unable connect authentication service LoL

League of Legends is a massively popular multiplayer online game. However, when trying to log in, several users have reported the Unable to connect to an authentication service error.

The error seems to be triggered due to connectivity issues and can be resolved by changing the DNS server.

In this article, we explore a couple of troubleshooting steps to help you resolve the unable to connect to the authentication service League of Legends error in Windows and other platforms.

How do I fix the authentication server error in League of Legends?

1. Check for service outage

The first thing to do is to make sure the issue is not at your end. To do this, check the League of Legends service status here.

Make sure you have selected the right region and then go through the services such as Game, Client, and Store to see if any of them are facing an outage.

If you see a red mark, you can only wait till the servers are back up again and running. If everything is in order, proceed to troubleshoot your network connection to fix the error.


2. Disable Windows Defender Firewall

Unable to connect to authentication service

  1. Press the Windows key + I.
  2. Click on Update & Security.
  3. Open the Windows Security tab from the left pane.
  4. Click on Firewall & Network Protection.
  5. Click on your currently active profile (Public in most cases).
  6. Toggle the switch to turn off Windows Defender Firewall.

Now that the firewall is off, try to login to League of Legends and check for any improvements. If it works, try adding League of Legends or the Game Launcher to Windows Firewall.

Add Game Launcher or League of Legends to White List

Unable to connect to authentication service

  1. Press the Windows key + R.
  2. Type control and click OK.
  3. In Control Panel, go to System and Security.
  4. Click on Windows Defender Firewall.
  5. From the left pane, click on Allow an app or feature through Windows Defender Firewall.
  6. Click the Change Settings button.
  7. Scroll down and make the Private & Public box is ticked for League of Legends launcher.
  8. Click OK to save the changes.

Before you relaunch League of Legends, make sure the Windows Defender Firewall is turned on. Login to your LoL account and check for any improvements.


3. Change DNS Server address

Unable to connect to authentication service

  1. Press the Windows key + R.
  2. Type control and click OK to open Control Panel.
  3. Go to Network and Internet > Network and Sharing Center.
  4. Click the Change adapter settings option from the left pane.
  5. Right-click on the network adapter and select Properties.
  6. In the Properties window, double-click on Internet Protocol Version 4 (TCP/IPv4).
  7. Select Use the following DNS server address.
  8. In the Preferred and Alternate DNS server field enter the following:
    8.8.8
    8.8.4.4.
  9. Check the Validate settings upon exit box.
  10. Click OK to save the changes.

Relaunch the League of Legends launcher and check if the unable to connect to authentication service error is resolved.


4. Use Hextech Repair Tool

League of Legends service error

  1. Download the Hextech Repair Tool.
  2. Run the installer.
  3. Follow the on-screen instructions to run the troubleshooter.

Hextech Repair Tool is an official LoL tool that allows you to reinstall and repatch the game, manage your firewall, show other known issues, etc.

After running the tool look for any issues shown by Hextech Repair Tool. The tool also recommends some fixes that you can apply to fix the error.

The unable to connect to authentication service League of Legends error is usually resolved by disabling the firewall or changing the DNS server address. You can run the Hextech Repair Tool for more troubleshooting steps.