Mac OS High Sierra External Display/Monitor not Working? Here’s the fix


High Sierra creates many issues on Mac each day. One of the important problem is external monitor not working after High Sierra update. Here I am going to tell you how to solve High Sierra external monitor issues.
The first thing you have to do is change your DisplayPort Adapter and try the new one. Because the problem may be in the DisplayPort Adapter.
Solution 1: SMC Reset
If your Mac has a non-removable battery,

  1. Shut down your Mac via Apple menu->Shut Down.
  2. Press and hold the Shift + Control + Option + Power Button simultaneously.
  3. Then release the keys at the same time.
  4. Press the Power Button to turn on your Mac.

If your Mac has a removable battery,

  1. Remove the battery out of your Mac.
  2. Press and hold the Power Button for 5 seconds.
  3. Insert the battery into your Mac.
  4. Turn on your Mac.

Solution 2: Reset NVRAM/PRAM

  1. Turn off your Mac via Apple menu->Shut Down.
  2. Press the Power Button to turn on your Mac.
  3. Then immediately press and hold the Option + Command + P + R keys simultaneously as quickly as possible after pressing the Power Button.
  4. Keep pressing until you hear the startup sound for the second time.

Solution 3: Update DisplayLink driver
One of the mac user said that updating DisplayLink driver solved his issue. Click here to update DisplayLink driver on your Mac.
If it doesn’t work out,

  1. Remove (uninstall) DisplayLink driver.
  2. Reboot your Mac.
  3. Install the latest DisplayLink driver and restart your Mac. Click Here to install the latest one.

Solution 4: Reinstall High Sierra
Reinstalling high Sierra may solve your problem.

  1. Turn off your Mac and press the Power Button to turn it on.
  2. Press and hold the Command + R keys simultaneously as soon as possible after pressing the Power Button.
  3. Keep pressing Command + R keys until the Apple Logo appears.
  4. After that Utilities windows will appear with 4 options. Tap “Reinstall macOS”.
  5. Tap “Continue”.
  6. You will be prompted to choose your hard disk/drive. If you are not asked to select your disk, tap “Show All Disks”. You may need to enter your Apple ID.
  7. Tap “Install”. Wait until the installation process is completed.
  8. Your Mac will restart after completing the installation.

Other Solutions:

  1. Downgrade macOS High Sierra.
  2. Restore your Mac to Factory Settings.

If you know any other solutions to fix this issue, let us know through your comments.

9:06 am

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