Check Whether Your Operating System Is Up to Date

Try attaching your MacBook to a power outlet to see whether this gives your laptop the juice it needs to power an external monitor. If you’re running your MacBook from its internal battery, it may not have enough power to push pixels to an external monitor. If you’re experiencing issues with an external display, then it’s always worth detaching your cable and adapter, then re-attaching them firmly. Even a slightly loose connection can prevent your Mac from recognizing the attached display. Just because a cable looks connected doesn’t mean that it is connected securely. Click “Restart,” then immediately close your Mac’s lid.

Select the “Apple” logo in your Mac’s menu bar.

Connect your Mac to the external monitor.

Some users have also reported positive results by switching their monitor on and off while also removing and reattaching the cable:įinally, if you’re using a MacBook, MacBook Air or MacBook Pro, you can try disconnecting while also closing your Mac:

Disconnect your adapter for 10 seconds.

Let’s start with the simplest fix: turn it off and then back on again! There are a few different techniques you can try: If you’ve followed the above instructions and your external display still isn’t working correctly, then you can try the following fixes: 1. Follow the instructions here to make sure your external monitor is connected properly. Let’s get the obvious out of the way first and make sure your external monitor and Mac are set up correctly. Before We Begin: Are You Sure Everything’s Connected Correctly?

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