Taking part in a League of Legends match can sometimes be a difficult task. Unlike other games where the lobby is buried within the game itself, League has a separate client interface that allows players to interact with their friends without actually launching the full game. Tiny bugs that affect the Riot client can prevent players from joining matches even if the servers are functioning properly. It’s unclear what the origins of the 0U error code are, but it has been affecting users around the world for some time. Riot quickly recognized the problem and confirmed that they were working on a fix, but that doesn’t mean you have to wait with your hands tied until the developer finds a permanent solution to the problem. fixes that you can try, but none of them can fix the error for good. The chances of the 0U error reappearing is still pretty high and you will have to wait for Riot to fix this minor issue.How to Fix League 0U Error Code Community managers or Riot members did not disclose an official fix method that gamers can try out, but community members who contacted the Riot support line were advised to run the Hextech Repair Tool. The Hextech Repair Tool is a utility program developed by Riot that automatically performs a troubleshooting session. The Hextech Repair Tool has several tools at its disposal to detect corrupted game files and can reinstall a patch or the game itself from scratch.Screengrab via Riot GamesScreengrab via Riot Games If these two options do not seem to resolve your issue, we recommend that you reinstall League through the Hextech Repair Tool. The tool also collects all of your league logs which you can send to Riot Support to help them identify the root of this issue, however, the above method is not guaranteed to work for everyone. Even players who managed to work around the error by reinstalling were greeted again after a while. Keep an eye on the support page to follow Riot’s progress regarding the error. If you are determined to play a game of League before bed, you can continue to try your luck by continually trying to log in after receiving the error.