Windows File Explorer Shows Icons Instead of Thumbnails — Every Fix

Windows Explorer not showing thumbnails is a common issue where images, videos, and documents display as generic icons instead of visual previews. The problem usually involves either a corrupted thumbnail cache, a Folder Options setting that disables thumbnails, or a folder too large for Windows to generate previews efficiently.

This guide covers every fix for Windows 11 and Windows 10.

Part 1. Quick Fix — Rebuild the Thumbnail Cache

The thumbnail cache is a hidden database Windows maintains in %LocalAppData%\Microsoft\Windows\Explorer. When this cache becomes corrupted or outdated, thumbnails stop displaying. Rebuilding it is the fastest fix.

Method 1 — Disk Cleanup (easiest):

1. Press Win + S → search for Disk Cleanup → run it
2. Select your system drive (usually C:) → click OK
3. In the list of files to clean, check Thumbnails
4. Click OK → confirm by clicking Delete Files
5. Windows deletes the thumbnail cache; thumbnails rebuild automatically as you browse folders

Method 2 — Manually delete cache files:

1. Press Win + R → type %LocalAppData%\Microsoft\Windows\Explorer → press Enter
2. Close all open File Explorer windows (important — close File Explorer completely)
3. Delete all files starting with thumbcache_ in this folder
4. Restart File Explorer: press Ctrl + Shift + Esc → find Windows Explorer → right-click → Restart

💡 Tip: If Disk Cleanup does not show a Thumbnails option, your cache may already be empty or the option is grayed out because cache files are in use. Use the manual deletion method instead.

Part 2. Check Folder Options — "Always show icons, never thumbnails"

A single Folder Options setting disables thumbnails globally across all folders. This setting is sometimes changed accidentally or by third-party software.

Steps:

1. Open File Explorer (Win + E)
2. Click View (top menu in Windows 10) or the three-dot menu (Windows 11) → Options
3. In the Folder Options dialog, click the View tab
4. Scroll through the advanced settings list
5. Find Always show icons, never thumbnails
6. Uncheck this option if it is checked
7. Click Apply → OK

Thumbnails should appear immediately after closing Folder Options.

🗣️ r/Windows11 user: "Spent an hour rebuilding caches and nothing worked. Turned out 'Always show icons, never thumbnails' was checked in Folder Options. One checkbox and everything was fixed immediately."

Part 3. Fix Performance Visual Effects Settings

Windows has a separate performance settings panel that includes a thumbnail option. If Windows was configured for "Adjust for best performance," thumbnails are disabled.

Steps:

1. Press Win + R → type sysdm.cpl → press Enter
2. Click the Advanced tab → under Performance, click Settings
3. In the Visual Effects tab, choose Custom
4. Scroll down and check Show thumbnails instead of icons
5. Click Apply → OK

⚠️ Important: Selecting "Adjust for best performance" in the Performance Options dialog disables thumbnails and many other visual effects. If your PC is slow and you previously chose this setting, manually re-check individual visual effects rather than switching back to "Let Windows choose" — this gives you performance without losing thumbnails.

Part 4. Fix Thumbnails for Specific File Types

Sometimes thumbnails work for photos (JPEG, PNG) but not for videos (MP4, MKV) or PDFs. This is typically a codec or viewer issue.

Videos not showing thumbnails:

Windows generates video thumbnails using installed codecs. If the Windows Media Player codec is missing for a video format (common with MKV, H.265):

1. Install the K-Lite Codec Pack (free) — includes thumbnail handlers for most video formats
2. Alternatively, install VLC media player — it registers a thumbnail handler for many video formats

PDF files not showing thumbnails:

Adobe Acrobat Reader registers a thumbnail handler for PDFs. If it is installed but PDFs still show no preview:

1. Open Adobe Reader → Edit → Preferences → General
2. Check Enable PDF thumbnail previews in Windows Explorer
3. Click OK and restart File Explorer

🗣️ r/techsupport user: "MKV files never showed thumbnails until I installed K-Lite Codec Pack. The thumbnail extractor for MKV is not built into Windows — you need a third-party codec pack."

Part 5. Fix: Folder Too Large for Thumbnail Generation

Windows has an undocumented threshold where thumbnail generation may slow or stop in folders containing thousands of files. This is not a bug per se — it is Windows throttling thumbnail generation to avoid performance impact.

Fixes:

• Break large folders into subfolders — 500–1,000 files per folder is a reasonable limit for smooth thumbnail generation
• Use Medium icons or Large icons view size instead of Extra Large icons — larger thumbnail sizes require more processing
• Run the thumbnail cache rebuild (Part 1) after reorganizing folders

💡 Tip: If thumbnails appear for the first 100–200 files in a folder but not the rest, this is the large-folder throttling issue. Scroll slowly through the folder to force Windows to generate thumbnails incrementally, or split the folder into smaller subfolders.

Part 6. Recover Missing Image Files With Ritridata

If thumbnails are not showing because the actual image or video files are missing — not just because of a cache issue — Ritridata can recover deleted, formatted, or lost image files from the drive.

Common scenarios where files are missing:

• Accidentally deleted photos or videos from a folder
• Drive formatted without backing up media files
• Files disappeared after a crash or corruption

Recovery steps:

1. Install Ritridata on a different drive or USB
2. Run a Deep Scan on the drive where files were stored
3. Filter by image types (JPEG, PNG, RAW, HEIC) or video types (MP4, MOV, MKV)
4. Preview recoverable files
5. Recover to a different location

💡 Tip: If thumbnails were showing yesterday but the folder now appears empty, the files may have been accidentally deleted. Run Ritridata's free scan immediately — the sooner you scan, the higher the recovery success rate.

FAQ

Q: Why do thumbnails disappear after a Windows update? Windows updates sometimes reset visual effects settings or clear the thumbnail cache during the update process. After a major update, check Folder Options (Part 2) and Performance Visual Effects (Part 3) — both settings can revert to defaults.

Q: How do I rebuild the thumbnail cache from the command line? Open Command Prompt as Administrator and run: taskkill /f /im explorer.exe to close File Explorer, then delete thumbcache files with del /f /s /q "%LocalAppData%\Microsoft\Windows\Explorer\thumbcache_*.db", then restart Explorer with start explorer.exe. This is equivalent to the manual method in Part 1.

Q: Why do thumbnails show for some images but not others? This usually indicates a codec issue — thumbnails work for file types with registered handlers (JPEG, PNG) but not for types without one (MKV, RAW camera formats, HEIC). Install the appropriate codec pack or viewer for the missing file types.

Q: Can a virus cause thumbnails to stop working? Some malware modifies registry settings related to thumbnail handlers. If thumbnails stopped suddenly after unusual PC behavior, run a malware scan with Windows Defender or Malwarebytes in addition to the thumbnail fixes above.

Q: How large can the thumbnail cache get before it causes problems? The thumbnail cache typically grows to 100–500 MB on an average system. On systems with large photo or video libraries, it can reach several gigabytes. Windows automatically manages cache size, but manual deletion (Disk Cleanup → Thumbnails) can resolve corruption issues when thumbnails stop updating.

Q: Why are thumbnails not showing on a new external drive? External drives create their own thumbnail cache. When you first connect an external drive with many files, Windows needs to generate thumbnails for the first time — this takes a few minutes. If thumbnails never appear, check that the drive letter and folder have full read permissions.

References

• Microsoft Support — Change how photos and videos are displayed in File Explorer
• Microsoft Support — Disk Cleanup in Windows
• K-Lite Codec Pack
• Adobe Acrobat Reader — Enable thumbnail previews
• Ritridata — Data Recovery Software