The Vanguard Error VAN 57 in League of Legends occurs when Riot’s anti-cheat engine, Riot Vanguard, fails to start correctly. This issue arises because ...

If you see Runtime error R6025 - Pure Virtual Function Call message when running an app, then one of these fixes is sure to help you.

If after a hardware change and you encounter Error Code 0x803FABB8, Donor hardware ID does not own operating system entitlement, see this fix.