Where is the Knight Online Option program?

Option.exe sits in the folder the game is installed in; for USKO that's something like C:\NTTGame\KnightOnlineEn. On the Steam version, right-click the game in your Steam library and use Manage > Browse local files. Run it with the game closed; saved settings apply the next time you start.

Some of these settings, like window mode, resolution and FPS, are also in Option > Graphic option while you play. Option.exe lets you change everything in one window before you log in.

Knight Online Game Option Setup window with graphics quality, DX Option, Visibility Range, Terrain View, Resolution and Color Depth, sound, language and Number of Effect settings
Knight Online Game Option Setup
Source / rights
Image / usage information: Knight Online — Mgame / NTTGame.

How do you play Knight Online in full screen?

  1. With the game closed, open Option.exe and untick Window Mode in the top right.
  2. Pick your monitor's resolution from the Resolution list.
  3. Press Save Changes and Start; the game opens in full screen.

In game you can also switch with the Use window mode box in Option > Graphic option. If the game resolution is larger than your desktop, you can't switch to windowed mode; the game shows "It's not possible to change the window mode because it exceeds the current resolution." Lower the resolution first.

How do you change the resolution? Game doesn't fit the screen

In Option.exe, pick the resolution from Resolution and the color depth (32 Bit) from Color Depth. In game, the current resolution sits between the arrows in Graphic option, and the arrows change it.

If the window spills off your screen in windowed mode, pick a resolution smaller than your desktop. On a 1920 x 1080 screen, 1600 x 900 fits with the taskbar still visible.

What does each Option.exe setting do?

Knight Online Game Option Setup settings
SettingWhat it does
Character / Object / Terrain (High, Low) Texture quality for characters, objects and ground
Show Weapon's effect Shows weapon effects
Show Area's Effect Shows area effects
Show Monster Script Shows monster speech balloons
Window Mode Ticked is windowed, unticked is full screen
HDR Blur HDR blur effect
DX Option DX11 or DX9 and the settings for each
Visibility Range View distance; lower it and distant things aren't drawn
Terrain View How far out the ground is drawn in detail
Resolution, Color Depth Game resolution and color depth
Sound Background music, sound effects, Duplicated Sound and how far away sounds are heard (Distance of Effect)
Language Language choice (English / Turkish)
Number of Effect How many effects are drawn at once
Window Cursor Uses the Windows cursor instead of the game cursor
Game Version Installed client version; Contents of the Update opens the update notes

OK saves your settings, Save Changes and Start saves and launches the game, and Cancel closes without changing anything. The DX Option settings are covered in the DX11 vs DX9 guide, and which ones to lower for frame rate in the FPS guide.

FAQ

Knight Online won't go full screen. What should I do?
Untick Window Mode in Option.exe and launch with Save Changes and Start. If you're switching in game, make sure your resolution isn't larger than your desktop.
Where are the Option settings saved?
Option.exe writes them to Option.ini in the game folder. Use Option.exe instead of editing the file by hand; a bad value can break your settings.
Why does the taskbar icon flash in windowed mode?
It's an alert added in August 2025: when the game runs in the background in windowed mode, the icon flashes if you take damage, make a sale in merchant mode or get a whisper. It doesn't work with Genie on, in windowed mode at maximum resolution, or in full screen.

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