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Second Monitor Not Detected

Beginner Display & Graphics Applies to: Windows 7, Windows 10, Windows 11

You plug in an external display and Windows doesn't see it.

Before you start: save any open work and note down what you were doing when the problem started — that context helps if you need to search further or ask for help.
  1. Press Windows+P and try cycling through the display modes (PC screen only, Duplicate, Extend, Second screen only) — sometimes it's detected but set to the wrong mode.
  2. Go to Display settings and click "Detect" under Multiple displays — this forces Windows to re-scan for connected screens.
  3. Try a different cable and port; a damaged HDMI/DisplayPort cable is a very common cause here.
  4. If using a docking station or USB-C hub, make sure it actually supports video output (some are charge/data only).
  5. Update your graphics driver, since multi-monitor detection issues are frequently fixed by a driver update.
Still not fixed? Send us the details and we'll help you dig further, or browse related guides in Display & Graphics.

Frequently Asked Questions

Does the cable type matter for detection issues?
Yes — a damaged or low-quality cable is a common, easy-to-overlook cause. Testing with a different cable, if you have one, is worth trying before assuming it's a driver or settings issue.
Why does my second monitor work sometimes but not after restarting?
This pattern often points to a loose physical connection or a power-saving setting that disconnects the monitor when it's idle — check the cable connection first, then look at your GPU's power management settings.

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