How to Fix a Second Monitor That Is Not Detected

When Windows Does Not Detect Your Second Monitor

Adding a second monitor increases productivity, but sometimes Windows does not recognise it. Here is how to fix it.

Check Physical Connections

Check Cables

• Make sure the cable is firmly connected at both ends
• Try unplugging and replugging the cable
• Check for bent pins or cable damage
• Try a different cable if available

Check the Monitor

• Make sure the monitor is turned on
• Check the monitor is set to the correct input (HDMI, DisplayPort, etc.)
• Look for a Source or Input button on the monitor
• Try the monitor with another computer to confirm it works

Check Your Computer

• Make sure you are using the correct port
• If using a laptop dock, check dock connections
• Some laptops need to be plugged in for external displays to work at full capacity

Detecting the Display in Windows

Force Windows to Detect

• Right-click on the desktop
• Click Display settings
• Scroll down and click Detect

Windows will scan for connected displays.

Use Keyboard Shortcut

Press Windows key + P to open display options:

• PC screen only: Only your main screen
• Duplicate: Same image on both screens
• Extend: Desktop spans both screens
• Second screen only: Only external display

Try selecting Extend or Duplicate.

Driver Solutions

Update Graphics Drivers

• Right-click the Start button
• Click Device Manager
• Expand Display adapters
• Right-click your graphics card
• Click Update driver
• Click Search automatically for drivers

Reinstall Graphics Drivers

If updating did not work:

• In Device Manager, right-click your graphics adapter
• Click Uninstall device
• Check Delete the driver software for this device if prompted
• Restart your computer
• Windows will reinstall basic drivers

For the best drivers, download from:

• Intel: For integrated graphics
• NVIDIA or AMD: For dedicated graphics cards

Adapter and Dock Issues

Using Adapters

If using an adapter (like USB-C to HDMI):

• Make sure the adapter supports video output
• Not all USB-C ports support video—check your computer specs
• Try a different adapter
• Some adapters require drivers

Docking Station Problems

• Check the dock is connected properly
• Try connecting the monitor directly to the laptop
• Update dock firmware if available
• Check dock manufacturer for driver updates

Display Settings Adjustments

Check Display Configuration

• Open Settings (Windows key + I)
• Go to System > Display
• If both monitors show, drag them to match their physical arrangement
• Set resolution for each display
• Set which monitor is the main display

Graphics Control Panel

For more options:

• Intel: Right-click desktop > Intel Graphics Settings
• NVIDIA: Right-click desktop > NVIDIA Control Panel
• AMD: Right-click desktop > AMD Radeon Settings

These panels offer additional display configuration options.

Common Issues

Monitor Detected But Black Screen

• Check cable is secure
• Check monitor is on the right input
• Press Windows + P and try different modes
• Check resolution is not set too high for the monitor

Display Flickering

• Check cable connections
• Try a lower refresh rate in Display settings
• Update graphics drivers
• Try a different cable

When to Contact IT

Contact helpdesk@netlumait.com.au if:

• None of these fixes work
• You need help choosing compatible cables or adapters
• The problem started after a Windows update
• Your work requires specific display configurations
• Multiple monitors are needed for your role

Need Help?

For monitor issues, contact helpdesk@netlumait.com.au or call 1300 521 162.