Quick look is feature on macOS that allows you to quickly preview a file. It supports quite a few different file formats and it’s so popular, there are apps that replicate it on Windows 10. The feature is great because it’s quick but if Quick Look tends to get stuck, or takes a long time to actually show the file you want to preview, it defeats the purpose of having it. If you have Quick Look stuck at loading, here’s how you can fix it.
Fix Quick Look stuck at loading
Open Finder and navigate to the following location;
Here, there should be a file called DropboxQL.qlgenerator if you use Dropbox on your Mac. Delete this file. If you do not use Dropbox on your Mac, you can skip this step however, if other cloud service apps are installed on your system, and one of them has a “qlgenerator” file in this location, delete it.
Next, Restart Finder. Tap the Command+Option+Escape keyboard shortcut, select Finder, and click Relaunch.
After you restart Finder, open Terminal and run the following command. You will need to authenticate with your user password.
sudo update_dyld_shared_cache -force
The command takes about a minute to complete but it may take less or more time depending on your system.
This next step might take a little time. Open Activity Monitor. You can open it from the Launchpad, or you can search for it via Spotlight. Once it’s open, look for all Quick Look processes. Tap the Q key and it will jump to the first process that begins with that letter. Keep tapping it until you find a Quick Look process. With the process highlighted, click the close button at the top (see screenshot below) to quit it. Repeat this for all Quick Look processes. Additionally, look for and quit all QuickLookSatellite processes.
Restart Finder again the same way you did before. When you next select a file and tap the Spacebar, the Quick Look preview will open much faster.
We’ve highlighted Dropbox as one of the apps that may cause problems with Quick Look but it may not be the only one. Other cloud service apps might also be to blame, and desktop apps i.e., those that do not work with an online service might also be causing the problem. As such, those apps may have a qlgenerator in the Quick Look folder. You can try deleting them. It won’t have any long or short term negative effects on your Mac. The files will automatically be generated again when you use Quick Look.