What causes Runtime Error in Knight Online?

  • Microsoft Visual C++ Redistributable packages are missing or damaged.
  • The graphics driver is old, especially with crashes in crowded places (Moradon, BDW, CZ) on DirectX 11.
  • A game file got corrupted during an update.
  • A mass wave: on September 19, 2026 many Steam players got a disconnect and then a Runtime Error the same morning; NTTGame's team investigated and players reported it fixed the same day.

How do you fix Runtime Error?

  1. Check whether everyone is getting it. If so, leave your files alone and wait for the announcement.
  2. Install the current Visual C++ Redistributable packages from Microsoft's official site, both x86 and x64, then restart.
  3. Update your graphics driver from the manufacturer's site (NVIDIA, AMD, Intel).
  4. If it crashes on DirectX 11, switch to DirectX 9: F10 in game → Graphic → DirectX Option → DirectX9 → APPLY. Details in Knight Online DX11 or DX9? Best stable DirectX settings.
  5. On the Turkish client reinstall from the official page; on Steam go to Library → Knight Online → Properties → Installed Files → "Verify integrity of game files".
  6. If it keeps happening, open a support ticket with a screenshot of the error box.

DLL not found errors

A "… .dll is missing" or "not found" error means a Windows component the game needs isn't there. Don't download single DLLs from DLL sites and copy them into system folders: it's a malware risk and rarely fixes anything. Install the full package from Microsoft instead.

DLL errors seen in Knight Online
FilePart ofWhat to install
d3dx9_43.dll, d3dx9_xx.dll DirectX 9 components Microsoft DirectX End-User Runtime
msvcp140.dll, vcruntime140.dll, msvcr*.dll Visual C++ runtime Visual C++ Redistributable (x86 and x64)
xinput1_3.dll DirectX controller component Microsoft DirectX End-User Runtime
dbghelp.dll Windows debug/report component; appears together with crash reports Look for the crash cause first (driver, DX11); install Windows updates

Official crash fixes

Some crashes were bugs in the game itself and got patched. The Steam version's maintenance notes list a crash when scrolling in the private message window (fixed June 7, 2023), a merchant-mode crash (September 11, 2024) and a crash when opening the "Temporary Item List" window (April 8, 2026). If the game crashes every time you open a certain window, it may be a bug like these; keep the game updated and report it.

Sound Device Fail

"Sound Device Fail" at launch means the game found no audio device. Set a playback device as default in Windows sound settings, plug your headset or HDMI audio back in, and update the audio driver. Players also report it on PCs running "freeze" software that resets the system on every boot (as in internet cafes). If there's simply no sound in game, check the sound options first: Knight Online Option.exe settings: full screen, resolution and window mode.

FAQ

What causes the C++ error in Knight Online?
The Visual C++ runtime shows that box when the game crashes. Missing Visual C++ packages, an old graphics driver and DirectX 11 are the usual causes.
The game closes with no error at all. What now?
Same steps: driver, Visual C++, switching to DX9 and repairing files. If it closes in crowded areas, lower the DX11 settings.
Can I just download the DLL and drop it in?
We don't recommend it. A single DLL can be the wrong version or carry malware; Microsoft's full package is both safe and permanent.
Does a Runtime Error hurt my account?
No, it has nothing to do with your account. Whatever you were doing when it crashed (setting up a merchant, for example) may be cut short, so check when you log back in.

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