How to Fix Brightness Not Working on Windows 11

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My Technician
Windows 11DisplayDriversFix

The Problem

The brightness slider is missing from Quick Settings, greyed out, or the screen ignores it completely. On laptops the Fn brightness keys may do nothing. This is almost always a display driver issue—especially a generic Microsoft Basic Display Adapter driver loaded after an update.

Screen also flickering or flashing? That's a separate fix: screen flickering on Windows 11. Using an external monitor, not a laptop panel? See the note near the end.

Quick Fixes (Try These First)

Use the Quick Settings Slider

Click the battery/network/volume cluster on the taskbar (Win + A) and drag the brightness slider. If it's missing entirely, jump to Step 1.

Restart After an Update

A cumulative update can swap your GPU driver for a basic one until the next reboot. Restart once before deeper steps.

The Fix: Step-by-Step

Step 1: Re-enable the Display Driver in Device Manager

  1. Right-click Start → Device Manager.
  2. Expand Display adapters.
  3. If you see Microsoft Basic Display Adapter, Windows is using a generic driver with no brightness control—continue to Step 2.
  4. Right-click your real GPU (Intel/AMD/NVIDIA) → Enable device if it's disabled.

Step 2: Update or Reinstall the Display Driver

  1. In Device Manager → Display adapters, right-click your GPU → Update driver → Search automatically for drivers.
  2. If that fails, right-click the GPU → Uninstall device (tick Attempt to remove the driver if offered) → reboot. Windows reinstalls a working driver.
  3. For the best result, download the latest driver from Intel, AMD, or NVIDIA directly.

Step 3: Re-enable the Monitor Driver

  1. In Device Manager, expand Monitors.
  2. Right-click Generic PnP Monitor → Enable device if it's disabled.
  3. If it's already enabled, right-click → Update driver → Search automatically for drivers.

Step 4: Turn Off Adaptive / Content-Adaptive Brightness

These features dim the screen on their own and feel like "broken" brightness.

  1. Settings → System → Display → Brightness.
  2. Untick Change brightness automatically when lighting changes and Help improve battery by optimizing the content shown (CABC).
  3. On some laptops, also disable Vari-Bright (AMD) or Display Power Saving (Intel) in the GPU control panel.

Step 5: Fix the Power Plan (Brightness Resets)

  1. Control Panel → Power Options → Change plan settings → Change advanced power settings.
  2. Expand Display → set Enable adaptive brightness to Off for both On battery and Plugged in.

A Note on External Monitors

Windows brightness controls only the built-in laptop panel. For a desktop monitor, use the buttons on the monitor itself—Windows can't dim most external displays in hardware.

Still Stuck?

  • Slider works but the screen is too dark even at 100%? The backlight may be failing—test the panel on an external monitor.
  • Persistent driver problems? Walk through how to update outdated drivers.