I can't patch my client (error 003)

After some research, I may have found a solution (it's working for me anyway)

C: > Riot Games > League of Legends > RADS > projects > lol_game_client

In that folder, delete the folder named "releases." After that, try launching your game again. Mine just finished patching fine.

Check this forum to fix the error. https://boards.eune.leagueoflegends.com/en/c/help-support-en/X6V5Znfk-error-code-003-13th-june-2018