Preview Not Working on Mac? Fixes That Actually Work

If Preview is not working on your Mac—whether it won’t open, crashes, or displays blank windows—the fix is usually a quick reset of its saved settings or a permissions repair. Below are the exact steps to resolve the most common Preview problems, followed by background on why they happen and how to avoid them.

Why Preview Fails on macOS

Preview is Apple’s built-in PDF and image viewer, and it relies on a few system services that can get out of sync. Most failures trace back to one of three causes:

Corrupted preferences or cache files – Preview stores window positions, recent files, and thumbnail settings in ~/Library/Containers/com.apple.Preview. A bad write here can cause crashes or a blank window.
Permission conflicts – After a macOS update or a migration from another Mac, Preview may lose access to your Desktop, Documents, or Downloads folders, so it appears to hang or show nothing.
System-level glitches – A stuck background process (like com.apple.QuickLook.ThumbnailsAgent) can freeze Preview when generating thumbnails.

First Try: Restart and Update

Before diving into deeper fixes, do the two simplest things:

Restart your Mac – This clears temporary system caches and kills stuck processes. Choose → Restart.
Update macOS – Go to System Settings → General → Software Update. Apple frequently ships bug fixes for Preview in point releases (e.g., macOS Sonoma 14.4 fixed a notorious Preview crash).

If Preview still won’t open, move to the reset steps below.

Reset Preview’s Preferences and Cache

This is the single most effective fix for Preview that “suddenly stopped working.” It does not delete your files—only settings like window size and recent items.

Quit Preview completely (press Cmd+Q).
Open Finder and press Cmd+Shift+G to “Go to Folder.” Paste this path and press Return:
~/Library/Containers/com.apple.Preview/Data/Library/Preferences/
Look for a file named com.apple.Preview.plist. Move it to your Desktop (don’t delete it yet).
Now go back to ~/Library/Containers/com.apple.Preview/Data/Library/ and open the Caches folder. Move everything inside to the Trash.
Restart Preview. If it works, you can delete the moved plist. If not, put the plist back and try the next step.

If you can’t see the Library folder, hold the Option key while clicking the “Go” menu in Finder—it will appear.

Check Folder Permissions

macOS uses a per-app permission system (TCC). If Preview lost its permission to access your files, it may open but show nothing or refuse to save.

Open System Settings → Privacy & Security.
Click Files and Folders in the left sidebar.
Find Preview in the list. Ensure the toggles for Desktop, Documents, Downloads, and any other folders you use are ON.
Also check Full Disk Access (same menu). If Preview is listed there, toggle it off and on again to refresh the permission.

If Preview isn’t listed, add it manually: click the “+” button, navigate to /System/Applications/Preview.app, and add it. Then grant the needed access.

Kill Stuck Background Processes

Sometimes Preview itself is fine, but a helper process is frozen. Use Activity Monitor (in /Applications/Utilities) to check for these names:

com.apple.QuickLook.ThumbnailsAgent
com.apple.ThumbnailAgent
Preview (if it shows as “Not Responding”)

Select any of these and click the “X” button to force quit. Then reopen Preview. This clears thumbnail-generation hangs without affecting your files.

When to Use Terminal (Advanced)

If the above fails, a deeper reset can help. This command clears Preview’s container folder (again, not your documents):

rm -rf ~/Library/Containers/com.apple.Preview

After running it, restart your Mac. Preview will recreate the folder fresh. Only do this if you’re comfortable with Terminal—it removes all Preview preferences, including any custom toolbar setups.

Alternatives to Preview

If Preview remains broken and you need to view or edit PDFs/images immediately, these built-in or free tools work as stopgaps:

Quick Look – Select a file in Finder and press the Space bar. This opens a preview without launching Preview.
Pages or TextEdit – Can open PDFs for reading, though not for annotation.
Photos app – For images, import them into Photos to view and do basic edits.

For full PDF editing, you could try a third-party app, but most require a paid license. The reset steps above resolve the issue for the vast majority of users.

Frequently Asked Questions

Why is Preview showing a blank white window?

This usually means the file is corrupted or Preview lost its permission to read the file’s location. Try opening a different file first. If that works, the problem is the file, not Preview. If every file is blank, follow the permission fix above.

Will resetting Preview delete my PDFs or images?

No. The reset only removes preference files and caches—never your documents. Your files stay exactly where they are. The only thing you lose are settings like window size and recent files.

Can I reinstall Preview?

Preview is part of macOS and cannot be uninstalled or reinstalled individually. The closest thing to a reinstall is the Terminal reset command in the advanced section above, which restores it to its default state.

Why does Preview crash when I try to edit a PDF?

Large PDFs (hundreds of pages) or PDFs with complex annotations can crash Preview. Try splitting the PDF first using Preview’s own “Export as PDF” on a smaller selection, or use the “Reduce File Size” filter in the Export dialog.

Does Preview work on macOS Sequoia?

Yes, Preview is included in all current versions of macOS, including Sequoia. If you’re having issues after upgrading to Sequoia, the reset steps above are especially likely to help because upgrades often leave stale preferences.

What if Preview won’t open at all?

If double-clicking does nothing, hold Control and click the Preview icon in the Dock, then choose “Quit” (if it’s running) and try again. If that fails, restart your Mac in Safe Mode (hold Shift at startup) and test Preview there. Safe Mode clears some caches and can reveal whether a third-party extension is interfering.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

More in this bed

The whole Tech How-To bed →