First check the connection and power supply, make sure the cable is plugged in, the monitor is turned on, and select the correct input source, and try replacing the cable or port. Secondly, restart the computer and re-detect the monitor, using the "Detection" function in Win P or display settings. Then update or reinstall the graphics card driver, update or uninstall the driver through Device Manager and restart. Finally adjust the BIOS or power settings, enable the display related options and turn off "Quick Boot". The above steps usually solve the problem that Windows does not recognize external monitors.

If your external monitor isn't being detected by Windows, you're not alone — it's a common issue that can happen for several reasons. The good news is that many fixes are simple and don't require advanced technical skills. Let's break down what to check and how to fix it.

Check Your Connections and Power Source

Before diving into software settings, start with the basics:

• Make sure both ends of the cable (HDMI, DisplayPort, USB-C, etc.) are plugged in securely.
• Confirm the monitor is powered on and set to the correct input source.
• Try using a different cable or port — sometimes the issue is simply a faulty connection.

It might sound obvious, but loose cables or incorrect input settings are more common than you think. Also, if you're using a docking station or USB hub, try plugging the monitor directly into your laptop or desktop to rule out interference.

Restart and Re-Detect the Monitor

Windows sometimes just needs a nudge to recognize new hardware:

• Press Windows P and see if the system detects the monitor. If not, click “Detect” under Display Settings.
• Restart your computer with the monitor already connected.
• Unplug and replug the monitor while the computer is running — this can trigger a re-detection.

Sometimes Windows will stop trying to detect after an initial failure, so manually asking it to search again can do the trick.

Update or Reinstall Graphics Drivers

Outdated or corrupted drivers are often the culprit when hardware isn't recognized:

• Open Device Manager ( Win X , then select Device Manager).
• Expand “Display adapters,” right-click your graphics card, and choose “Update driver.”
• Alternatively, uninstall the driver completely, then restart your PC — Windows should reinstall it automatically.

You can also visit your laptop/desktop manufacturer's website for the latest driver version tailored to your specific model.

Try Adjusting BIOS or Power Settings

In some cases, deeper system settings may interfere:

• Enter your BIOS/UEFI (usually by pressing F2, F10, or Delete during startup) and make sure any display-related options are enabled.
• In Windows power settings, disable features like "Fast Startup" temporarily — they can occasionally prevent proper hardware detection.

Also, if you're using a laptop, ensure it's not in tablet mode or set to only use the built-in display.

Basically, troubleshooting a monitor not being detected comes down to checking connections, restarting detection, updating drivers, and occasionally tweaking system settings. It's usually something small — but easy to overlook.

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