External Display Not Working? Try These 14 Fixes for macOS

1. Why won't my Mac recognize my external monitor?
2. How do I reset my external display on my Mac?
3. Why is my Mac not working with HDMI?
4. How do I get my MacBook Air to display on an external monitor?
5. How do I connect my MacBook to an external monitor?
6. How do I reset my external monitor?
7. Why is my Thunderbolt display not working?
8. How do I reset my Mac monitor?
9. Why does my monitor say no signal?
10. How do I reset the SMC on my MacBook Pro?
11. Why is HDMI only showing wallpaper Mac?

Why won't my Mac recognize my external monitor?

If you're using an Apple notebook, try connecting its power adapter. Make sure the external display's power cable is securely connected and that your display is turned on. ... If possible, check to see if using a different display or a different adapter works. Try using a different cable that you know is in working order.

How do I reset my external display on my Mac?

After your Mac starts up, choose Apple menu > System Preferences, click Displays, then click Display. For the Resolution option, select “Default for display.” Restart your Mac normally.

Why is my Mac not working with HDMI?

If your Mac doesn't recognize your HDTV, display, or other HDMI device after making the connection: Turn off the HDMI device while your Mac is turned on. Unplug the HDMI cable from your Mac, then plug it in again.

How do I get my MacBook Air to display on an external monitor?

Mirror your displays

Make sure that your external display is turned on and connected to your Mac. Choose Apple menu  > System Preferences, click Displays, then click the Arrangement tab. Make sure that the Mirror Displays checkbox is selected.

How do I connect my MacBook to an external monitor?

The monitor's settings are also available.

1. Plug in your external display to a power source.
2. Plug your external display into your MacBook.
3. Ensure the external display (or both, if you're able to use two displays) is active and on.
4. From your Mac menu bar, select the Apple logo at the top left corner.

How do I reset my external monitor?

To Clear and Reset External Display Cache in Windows 10,

Right-click on the subkey Configuration and select Delete from the context menu. Now, delete two other subkeys, Connectivity and ScaleFactors. Restart Windows 10 to make the changes done by the Registry tweak take effect.

Why is my Thunderbolt display not working?

The main problem is most likely coming from your connected computer. Take the thunderbolt cable and unplug it from your connected computer. Wait a few seconds and then plug the cable back in. If the problem continues, try restarting your computer.

How do I reset my Mac monitor?

Press and hold the Command-Option-P-R keys immediately after you hear the startup sound. Hold these keys until the Mac restarts and you hear the startup sound for a second time. Release the keys.

Why does my monitor say no signal?

If Monitor Displays “NO SIGNAL” or “SELF TEST” – this means that your computer monitor is working properly but isn't getting a signal from the computer. Start troubleshooting your issue by ensuring that both ends of the video cable that goes between your computer and your monitor are pushed in the whole way.

How do I reset the SMC on my MacBook Pro?

How to reset the SMC on Mac notebooks:

1. Choose Apple menu > Shut Down and wait for your Mac to shut down.
2. Press Shift-Control-Option on the left side of the built-in keyboard, then press the power button at the same time. ...
3. Release all keys.
4. Press the power button again to turn on your Mac.

Why is HDMI only showing wallpaper Mac?

ferrarr said: If you open System Preferences, then select Display. There you will have the choice to Expand display, which will set the TV up as another screen to use, or, Mirror display, which will show the same as your MacBook Pro screen.