League of Legends Error Code 999: How to Fix It

Medium 30-60 minutes High Severity Verified June 2026
Error Code
Error Code 999
Brand
League of Legends
Product Type
game
Severity
High
DIY Difficulty
Medium
Estimated Fix Time
30-60 minutes
Error Code 999 in League of Legends indicates an account-related authentication problem preventing you from logging in. This error typically occurs due to server issues, account security flags, or corrupted client data that needs to be refreshed.
Ad

Tools You'll Need

How to Fix Error Code Error Code 999

  1. Check Riot Games Server Status

  2. Restart League of Legends Client

  3. Clear Client Cache and Data

    Back up your game settings before deleting config files as you may need to reconfigure your preferences
  4. Run League Client as Administrator

  5. Disable Firewall and Antivirus Temporarily

    Remember to re-enable your security software after testing and add proper exceptions
  6. Reset Network Settings

  7. Try Different Network Connection

  8. Reinstall League of Legends

    This will require re-downloading the entire game which may take several hours depending on your internet speed

Parts You May Need

Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Stable internet connection
Check Price on Amazon
Alternative network connection
Check Price on Amazon
Ad

When to Call a Professional

Contact Riot Games support directly if Error Code 999 persists after trying all troubleshooting steps, as this indicates a server-side account authentication issue that requires manual intervention from Riot's technical team.

Frequently Asked Questions

What does League of Legends Error Code 999 mean?
Error Code 999 indicates an account authentication problem that prevents you from logging into League of Legends. It's typically related to server issues, account security flags, or corrupted client data.
Is Error Code 999 a permanent account ban?
No, Error Code 999 is not a ban. It's an authentication error that can usually be resolved through troubleshooting steps or by contacting Riot support for account verification.
How long does it take to fix LoL Error Code 999?
Most cases can be resolved within 30-60 minutes through basic troubleshooting. However, if it requires Riot support intervention, resolution may take 24-48 hours.
Can I play on a different account while Error 999 is happening?
If the error is account-specific, you may be able to log in with a different account. However, if it's a client or network issue, all accounts may be affected until resolved.
Does reinstalling League of Legends delete my game progress?
No, your game progress, champions, skins, and rank are stored on Riot's servers and tied to your account. Reinstalling only affects local client files and settings.