Many players have faced the problem of entering the game with an error 170000
To fix this follow this instruction:
The root cause seems to be a login load issue as everyone is trying to get in.
To resolve, make sure to completely shut down LoR, including going into Task Manager and making sure it is ended there as well (should appear as Riot Client). Then try relaunching. Repeat until you get in normally.
If not working, try to restart your router and PC