How to Fix: League of Legends Error Code 003

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League of Legends error code 003 is one of the most frustrating problems you have to deal with in the game because it only occurs when a new patch is added. While you should be enjoying the new content and understanding the evolving meta, you are instead dealing with troubleshooting.

Here are the best ways to fix League of Legends error code 003 so you never have to experience problems on patch day again.

What causes error code 003 in League of Legends?

Server problems: In some cases, the error is due to server issues. Servers are often undergoing maintenance to update, or there may be a specific error that prevents you from installing the game.

Windows Update: In some cases, an error may occur when a Windows update is waiting to be installed. It is important to make sure that all Windows updates are installed and that the update queue is empty. If there are updates waiting to be installed, this error may occur.

Internet problem: If the problem occurs because the Internet connection is established from a remote location not authorized by the server, or if the connection is considered suspicious by the server, files cannot be installed. Therefore, it is recommended to use a VPN for the connection or try to establish another connection.

Antivirus: In some cases, antivirus installed on the system may prevent the launcher from installing the patch/game, leading to an error. This usually happens because of a false antivirus that reports certain files on your computer as suspicious, preventing the launcher from installing them.

Corrupted content: The content downloaded by the launcher may have been corrupted, causing an error when applying the fix.

Important files can often be corrupted if the connection is unstable or if the Internet is quickly disconnected and reconnected while downloading. This can also cause League of Legends to fail to open.

How to Troubleshoot League of Legends error code 003

Configure your DNS

Configure DNS on Windows computers:

1. Go to Control Panel > Network and Internet > Network and Sharing Center > Change Adapter Settings > go to your active network adapter (your active Internet connection).
2. Right click on it > select Properties > go to Internet Protocol Version 4 > select Properties.
3. Under Use the following DNS server address, enter the following DNS numbers: 8.8.8.8.8 for the preferred DNS server and 8.8.4.4 for the alternate DNS server.
4. Now run the command line as administrator and type the following command: ipconfig /flushdns > press Enter
5. Reboot your computer and start again.

Configure DNS on Mac computers:

1. Click on the Apple icon > go to System Preferences > select Network.
2. Select your active connection > click Advanced > select DNS
3. Write down your existing settings.
4. Now enter 8.8.8.8.8 on the first line and 8.8.4.4 on the second line under DNS Server.
5. Click OK > Apply and test your game.

Run the game as an administrator

Make sure you run League of Legends as an administrator.

Here’s how:

1. Right-click the game icon on your desktop > go to the “Compatibility” tab.
2. Turn on the option Run this program as administrator
3. Restart LoL

Delete the contents of the release file

1. Go to Rads > Projects > lol_game_client > releases
2. Delete the release file, not all files, otherwise, you may delete the entire game.
3. This will delete the last patch and your computer will download it again.
4. Restart the game.
5. Keep in mind that deleting the contents of this file may take some time, depending on what is stored in it.

Turn off your firewall

Sometimes your firewall can prevent you from connecting to game servers. Disable it and see if error 003 persists. If disabling the firewall solved the problem, add LoL to your exclusion list so you can continue to use the firewall while you play.

Disable the firewall in Windows:

1. Go to Control Panel > System and Security > Windows Firewall.
2. Go to Allow application or function through Windows Firewall.
3. Select Change settings > scroll down the list of programs and find LoL > check the appropriate checkbox.
4. Go to Allow another program > find LoL in the list > add it > click OK.

Disable the firewall on your Mac:

1. Click the Apple menu button > go to System Preferences > View.
2. Go to Security and Privacy > select the Firewall tab > Disable Firewall.
3. Restart the game and see if the problem persists.

Note: Speaking of security settings, don’t use a VPN or proxy to connect to a League of Legends server. These tools are known to cause a lot of connection problems.

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