Fix: File Icon Preview Thumbnails Not Showing on MacOS

Struggling with file icon preview thumbnails not showing on your Mac? This can happen due to settings or an outdated macOS.

We’ll guide you through simple solutions to fix this issue and get your thumbnails back.

Let’s start!

1. Ensure That the Entire File is Downloaded

If the icon preview of a file isn’t showing on the Finder menu, the very first thing that you should do is check whether the entire file is downloaded or not.

Regardless of the browser you’re using, if the file or media is still downloading, its thumbnail won’t show on Finder till the download process is complete. 

However, if you’re sure that the files are fully downloaded, but the file icon preview thumbnails are still not showing on macOS, head to the next method from this guide to fix it. 

2. Enable Icon Preview

The older macOS versions displayed a simple file icon rather than thumbnail images. But with the newer OS X versions, Apple has enabled the file icon preview thumbnails by default.

So, if you’ve accidentally tweaked this feature off, it may be the reason behind the File icon preview thumbnails not showing on macOS. 

Here’s how to toggle on the icon preview feature on Mac: 

1. Click on Finder from the dock.
2. Go to View from the menu bar at the top of the screen.
3. Then, select Show View Options from the list.

4. Click on the Show icon preview box to enable it.

After that, go back to the Finder menu to see the file icon preview thumbnails. 

3. Force Quit and Relaunch Finder

Occasionally, a temporary glitch in the Finder app could be the reason behind the issue of File icon preview thumbnails not displaying on macOS.

If you’ve already activated the icon preview feature but still face the problem, try force-quitting the Finder app. Then, relaunch it after a short pause, which may resolve the issue:

1. Click on Finder on your Mac.
2. Then, go to Applications.
3. Locate the Utilities folder and double-click on it.
4. From there, launch the Activity Monitor by double-clicking on it.

5. Go to view from the Activity Monitor’s menu bar.
6. Now, click on All Processes.
7. Search for ‘com.apple.quicklook.ThumbnailsAgent’ in the search bar located at the top right corner and press the Enter key.
8. Click on the result and select the X icon on the taskbar.

9. A dialog box will appear. From there, click on the Force Quit button.
10. After that, go to the Apple menu and click on Force Quit Activity Monitor.
11. Choose Finder from the list of applications and select Relaunch.

Now, you should be able to see the file icon preview thumbnails in the Finder menu. If not, move to the following method to resolve your problem. 

5. Ensure You Have an Active Internet Connection

A stable internet connection is essential for viewing file thumbnails on macOS.

First, it’s needed to fully download files from the internet to see their previews. Second, for cloud storage files in Finder (like Microsoft OneDrive or Google Drive), a constant internet connection is necessary because these files aren’t stored locally.

If you’re facing issues, check your internet speed. Switching to a 5GHz Wi-Fi band can improve connectivity and help resolve the thumbnail preview issue.

6. Regenerate Finder PLIST File

The Finder PLIST files on Mac store your app preferences, but they can sometimes get corrupted and need to be deleted to fix issues with Finder.

To resolve the File icon preview thumbnails not showing on macOS, try deleting the Finder PLIST file using the steps below:

1. First, launch Finder on your Mac.
2. Next, select Go from the menu bar.
3. Click on Go to Folder from the list of options.

4. Then, enter the following command:

~/Library/Preferences

5. Look for the ‘com.apple.finder.plist’ file and right-click on it.
6. Select the Move to Bin option.

7. After that, press Command + Shift + Delete to empty your Mac bin.
8. A confirmation box will appear on the screen. Click on the Empty Trash button to confirm.
9. Lastly, reboot your Mac. The rebooting process will regenerate the Finder PLIST File.

Once done, check if you can see the icon preview thumbnails for files on the Finder menu. 

7. Activate Safe Mode. 

Another troubleshooting method that may help resolve the file icon preview not working is to boot your Mac in Safe Mode.

This way, you can determine if the issue was caused by any apps that may have interfered with the Finder app functionality.

Ffollow the steps below to activate Safe Mode. For an Apple Silicon Mac:

1. First, go to the Apple menu, then select Shut Down to power off your Mac.

2. Once the Mac is completely shut down, press and hold the Power button to turn on your Mac.
3. Let go of the Power button once you see the Startup options appear on the screen.
4. Then, choose your Startup disc.
5. Press and hold down the Shift key as you click on Continue in Safe Mode.

6. Finally, sign in to your Mac.

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For an Intel Processor Mac:

1. Press the Power button to turn on your Mac.
2. As your Mac restarts, press and hold down the Shift key.

3. Once the Login window appears, let go of the Shift key and sign in to your Mac. You have now activated Boot Mode.

Once in Safe Mode, check if you can preview thumbnails of files on macOS. If not, move to the next method mentioned in this guide. 

8. Clear Cache via Terminal Command

If the file icon preview thumbnails are missing for both the Finder and Mac docks, the issue may be widespread. For this reason, consider clearing the cache using the below Terminal commands to quickly resolve the problem:

1. First, press the Command + Space shortcut keys from your keyboard to launch Terminal.
2. Run the following commands one by one:

qlmanage -r cache

qlmanage -r

killall com.apple.quicklook.ThumbnailsAgent

killall Dock

Make sure to press Enter after each command to run it. This will clear the cache and fix the File icon preview thumbnails not showing on macOS.

9. Update macOS. 

Occasionally, Apple releases patch updates to introduce new features and eliminate various bugs.

So, if you’re facing the File icon preview thumbnails not showing on macOS issue, consider checking if there’s a macOS update. If there’s one available, update your Mac and see if it fixes the problem. 

1. Go to the Apple menu at the top left corner of the screen.
2. Next, click on System Preferences.

3. Once the window opens, select Software Update.
4. If there is any pending update, click on Upgrade Now.

Since updating your macOS may take a while, we suggest you fully charge your Mac and connect to a strong internet connection before starting the downloading process.

This sums up our guide on how to fix File icon preview thumbnails not showing on macOS. If you have any queries, feel free to use the comments section below. We’ll be happy to assist you further. 

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