If you’ve landed on this page, you likely have just installed a new Mortal Kombat game— Mortal Kombat 1 (the reboot) or MK11 —only to be greeted by a cryptic error box that reads something like: or "Fatal error: CoreErrorsOpen failed – Null core from stream" This error typically appears at launch, before the game even shows the logos, or crashes immediately after the splash screen. It is not a standard Windows error; it’s an internal Unreal Engine 3 or 4 error (depending on the game) related to how the game reads its core configuration files.
A error means the engine tried to access a core configuration object, but that object was empty (null). “Open failed” indicates the game couldn’t read a necessary .ini or .cfg file. null coreerrorsopen failed mortal kombat new
Last Updated: 2026 Affected Games: Mortal Kombat 1 (2023), Mortal Kombat 11, Mortal Kombat X Platforms: PC (Steam, Epic Games) If you’ve landed on this page, you likely
→ (And by that, we mean finish the error.) “Open failed” indicates the game couldn’t read a
Have another variation of “coreerrorsopen failed”? Screenshot it and post on the official WB Games support forum—mention “null core” for faster triage.