Check Your Display Preferences
Regardless of your MacBook Pro or other Mac model, it’s not uncommon to experience a display connectivity issue when hooking up an external monitor. If you’ve hooked up an external display to your Mac and nothing is happening (just a blank or black screen appears), your display preferences are the first place to look.
Adjust Display Resolution Settings
Another possible reason your external display isn’t detected (or you end up seeing a dreaded pink screen) could have to do with display resolution and brightness settings.
Double-Check Display Cable Connections
If your Mac still doesn’t recognize your display after prompting the Detect Displays scan and adjusting resolution and brightness, it can help make sure connecting cables are in order.
Make Sure You Have the Right Adapter
Depending on your particular Mac, chances are you’ll find yourself working with third-party hubs, adapters, or display software to extend your display. Before using, it’s important to check for compatibility with your particular model.
