Some of Mac Users had reported a problem that, before upgrading to High Sierra, their Mac recognized the external monitor. But after upgrading it, they couldn’t recognize the external monitor. It seems to be a frustrating issue for you. Following are some of the tricks to be suggested to get rid of this serious issue. Come on let’s check out…!
Fix 1: Reset SMC
If your Mac has a non-removable battery,
- Firstly, shut down your Mac via Apple menu->Shut Down.
- Then press and hold the Shift + Control + Option + Power Button simultaneously.
- Now you have to release the keys at the same time.
- Finally, press the Power Button to turn on your Mac.
If your Mac has a removable battery,
- First, remove the battery out of your Mac.
- Then press and hold the Power Button for 5 seconds.
- Now insert the battery into your Mac.
- Finally, turn on your Mac.
Fix 2: Reset NVRAM/PRAM
- Turn off your Mac via Apple Menu->Shut Down.
- Press the Power Button to turn on your Mac.
- Then immediately press and hold the Option + Command + P + R keys simultaneously as quickly as possible after pressing the Power Button.
- Keep pressing until you hear the startup sound for the second time.
Fix 3: Contact Apple Support
If your device is under Warranty Status, then you can contact Apple Support for further help.
Fix 4: Update DisplayLink Driver
- Go to Finder -> Settings.
- Tap on DisplayLink -> Uninstall.
- Download the latest version of DisplayLink.
- Wait for few seconds and then restart your device.
See also: MacBook Pro does not detect external monitor display, fix
Fix 5: Restart your Mac
- First, shut down your mac.
- Then Press and hold Power Button+Command+Option+R+P keys simultaneously until you hear the startup sound for the second time.
Fix 6: Downgrade macOS High Sierra.
Note: Before downgrading to Sierra, it is advisable to download Mac OS Sierra from the Mac store and then take a backup of all your data.
- Connect your Mac to the internet using Wi-Fi or Cellular Data
- Restart your Mac in the Recovery mode
- Press Command + R until your Mac reboots
- Press Disk Utility on the Mac OS X Utilities Screen
- Press Continue and then select your Startup Disk
- Tap Erase (at the bottom of your screen)
- Enter a disk name for the file to be deleted
- Select Mac OS Extended (Journaled) from the Format option
- Tap Erase
- Change your monitor settings from DisplayPort to HDMI.
- Disconnect and then reconnect your monitor and everything that connects with.
- Make sure that the USB port on the connector is open and not with a cord attached.
- Restore your mac to factory settings.
Hope any one of the above fixes will be helpful to you. If you find this article as useful, then kindly share your experience with me through your comments below. Thank You…