How to Fix Games Running in Windowed Mode Instead of Fullscreen

What Causes This?

Games usually open in windowed mode because the in-game display setting changed, Windows is overriding fullscreen behavior, or another app is interfering with focus. Common triggers include graphics driver changes, multi-monitor setups, Game Bar or overlays, and Windows fullscreen optimizations not working properly with a specific game. In some cases, the game is actually using borderless windowed mode, which looks similar to fullscreen but behaves differently.

Common Symptoms

• The game opens with a title bar, borders, or visible taskbar
• Pressing fullscreen in the game settings does not stay applied
• Alt+Tab feels too fast, suggesting the game is not in exclusive fullscreen
• Performance feels worse than usual, with more stutter or input delay
• The mouse can move onto a second monitor during gameplay

How to Fix It Manually

1. Switch the game to fullscreen in its own settings

   • Open the game and go to Settings, Options, or Video/Display.
   • Look for Display Mode and change it to Fullscreen instead of Windowed or Borderless Windowed.
   • Apply the change and restart the game if prompted.

2. Use the Windows fullscreen shortcut

   • While the game is open, press Alt + Enter.
   • Many PC games use this shortcut to toggle between windowed and fullscreen mode.
   • If nothing happens, continue with the next steps.

3. Check the game’s launch options

   • If you use Steam, open Steam > Library.
   • Right-click the game > Properties.
   • In Launch Options, remove commands that force windowed mode, such as -windowed, -w, or -sw.
   • If needed, try adding a fullscreen launch option supported by the game, such as -fullscreen.
   • For other launchers, check the game settings for similar startup arguments.

4. Disable Fullscreen Optimizations for the game

   • Close the game first.
   • Find the game’s .exe file. If needed, right-click the game shortcut > Open file location.
   • Right-click the game executable > Properties > Compatibility tab.
   • Check Disable fullscreen optimizations.
   • Click Apply > OK, then launch the game again.
   • This can help when Windows forces a hybrid fullscreen mode that causes problems.

5. Close overlays and background apps that can break fullscreen

   • Open Task Manager with Ctrl + Shift + Esc.
   • End non-essential apps that may hook into games, such as screen recorders, RGB tools, chat overlays, or FPS counters.
   • Also check these built-in features:
     • Open Settings > Gaming > Xbox Game Bar and turn it Off if you do not use it.
     • Open Settings > System > Notifications and disable distracting pop-ups during gaming.
   • Relaunch the game and test fullscreen again.

6. Update or reinstall your graphics driver

   • Right-click Start > Device Manager.
   • Expand Display adapters, right-click your GPU, then choose Update driver.
   • If the issue started after a driver update, install the latest driver directly from NVIDIA, AMD, or Intel instead.
   • A bad or incomplete driver install can stop games from switching display modes correctly.

7. Check resolution and multi-monitor settings

   • Right-click the desktop > Display settings.
   • Make sure your main monitor is set as Make this my main display.
   • Confirm the monitor is using its Recommended resolution and refresh rate.
   • If needed, temporarily disconnect the second monitor and test the game again.

Fix It Automatically with Kudu

Kudu can automatically detect Windows settings, background apps, and gaming-related conflicts that stop games from entering true fullscreen mode. It helps remove common interference, optimize system behavior, and restore cleaner game launches without digging through multiple menus yourself.

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