The screenshot feature built into macOS requires no additional software; it should just work. If it stops working, there are a few places to look for answers-starting with the keyboard. If this accessory is functioning properly, look elsewhere.
Whether you use the tried-and-true keyboard shortcuts for taking screenshots or prefer to go through the Preview app or the Screenshot app (in Mojave or later) for that purpose, one of these fixes should get your Mac's screenshot feature up and running.
Information in this article applies to macOS Catalina (10.15) through macOS Sierra (10.12), except as noted.
If everything else works correctly on the Mac, the keyboard is working correctly and isn't the problem. There are several other things you can do to pinpoint the reason why your Mac's screenshot function won't work.
Turn off the Mac and turn it back on. Running a Mac for long periods without shutting it down can cause it to perform inefficiently or prevent certain apps from working properly.
If the screenshot feature on your Mac isn't working, shut down the Mac and turn it on again. Then take a screenshot according to your preferred method, whether that's keyboard shortcuts or the Screenshot app.
Check the screenshots keyboard shortcuts. These settings are on by default. They may have been switched off at some point or set to keyboard combinations other than the defaults.
To check this, go toSystem Preferences>Keyboard>Shortcuts. There you can see whether keyboard shortcuts have been turned off or reassigned to other actions.
Reset the NVRAM. Like a simple restart, resetting the non-volatile random-access memory (NVRAM) can sometimes resolve issues with core Mac apps and functionality. This memory is responsible for controlling many of the internal settings of the computer.
Confirm the location for saving screenshots in the Screenshot app. The default is to save screenshots to the Desktop. If you changed that setting, your screenshots may be hiding somewhere you haven't looked. Check the location on the Screenshot app's floating menu bar.
If you prefer a manual approach, use Terminal to set the destination for screenshots and other files.
Check Your Dropbox settings. If you have Dropbox on your Mac, you may have set it so that screenshots save to your Dropbox rather than your Mac's desktop.
When you can't take a screenshot on a Mac, you're missing a valuable tool for troubleshooting and communicating ideas through email and text messages. Since it's rare that screenshots don't work on a Mac, it may be easy to discover why your Mac isn't performing as expected.
It's wise to start by confirming that the keyboard is responsive. If you notice issues with specific keys or momentary unresponsiveness, try these Mac keyboard troubleshooting tips.
Other places to look include the Mac's keyboard shortcut settings for screenshots and the built-in Screenshot app.