It’s day two of Tech 911—the working-from-home edition—and I’m back to tackle even more of your tricky troubleshooting. Remember, if you’re having any issues with your work-from-home setup, I encourage you to leave a comment to this post (or this post!), or shoot me an email. I’ll try to answer your questions as best I can, because a good puzzle helps break the monotony of a quarantine.
For today, I’m taking a question from Lifehacker commenter crs486, and it involves my least-favorite topic: getting multiple displays to play nicely.
“i cannot for the life of me get a 2nd monitor to work. it is connected using an adapter as my machine does not have a connection. i’ve also tried HDMI and that method also does not work. the monitor works fine hooked up to other machines. does it make a difference if this laptop is traditionally docked? i am not using the docking station.”
Hmm. There’s a bit to unpack with this question, so let’s begin. By “have an adapter,” I presume you mean that you’re doing some kind of USB-to-whatever adapter to force a second video connection on a laptop that doesn’t otherwise have its own HDMI port or DisplayPort—or Thunderbolt, for that matter.
I’m glad you already tested the monitor with other machines, as that rules out any mechanical defect or other pesky issue with your hardware. We can narrow down to the adapter and the connection itself, which is where I suspect the problem lies.
You didn’t specify, but I’m assuming your system doesn’t have a USB-C connection. If it does, this should be easy. A simple USB-C to HDMI adapter is all you need to get going. In your case, there might be an issue with the adapter itself, which is something you might want to check on, say, Amazon, or anywhere else that’s selling it. If a lot of people are reporting issues with the adapter, it’s possible that it’s a junky device. It certainly happens, and a new adapter might be all you need. (I use this one, and it’s always worked well for me.)
If your laptop only has USB 2.0, I’m almost willing to bet that something is funky with your adapter. Either it’s underpowered, it just isn’t working right, or there’s some kind of incompatibility with your operating system. Said adapter likely has drivers that you’ll need to install in order for your operating system to use it, so you might want to check the manufacturer’s website for those. And if I’m right, a simple “USB to HDMI” cable isn’t going to work in this scenario—I’m assuming you don’t have that, as the adapter is the critical component. If so, there’s your problem right there.
You mentioned that your laptop has a docking station. I’d investigate that, as it’s possible said station has a built-in HDMI port or other display connection that you can use to hook up a second monitor. (I’d be surprised if it didn’t, but you never know!)
Beyond that, it’s possible that the hardware connection is working properly and, for whatever reason, your operating system doesn’t recognize your second display. There might be some keyboard command you need to hit in order to enable a multi-monitor setup (typically Function + whatever key has the icon that looks like two rectangular displays separated by a vertical bar in the middle). That, or you might need to set something up in your OS directly.
In Windows 10, you should find any relevant settings within the Settings app Display. Look for the “Multiple displays” section and make sure you’re duplicating or extending your display, not simply showing it on your laptop (Windows Key + P is a useful shortcut for checking this, too.) If you’re on Windows 7 or Windows 8, you’ll want to right-click on your desktop and select “Screen resolution” to find similar settings.
In macOS, simply click on the Apple logo in the upper-left corner, then System Preferences, and then Displays. If your system detects the second monitor, you’ll find all the options for configuring your setup within this screen. If you don’t see anything, try holding down the Option key and selecting the now-visible “Detect Displays” button.
If you’re still not finding any success, I’m still willing to bet that it’s your adapter. You can continue the process of testing out new cables and adapters to see if this works, or you can abandon ship. I’d at least give it one more go before you do the latter, but try checking the adapter on another laptop/monitor setup—even if you have to drop it off in a friend’s mailbox during your work-from-home break/quarantine.
If your laptop is ultimately to blame, you might have to go single-screen for the time being, annoying as that is. Or perhaps you can try using a third-party app to hook up an tablet as a secondary screen, if you must have that extra display.
Do you have a tech question keeping you up at night? Tired of troubleshooting your Windows or Mac? Looking for advice on apps, browser extensions, or utilities to accomplish a particular task? Let us know! Tell us in the comments below or email firstname.lastname@example.org.