Whats happening when i open folders

• Please attach a screenshot or short video showing the problem.
• Does it happen with every folder or only certain ones (large picture folders, network shares, folders with many files)?
• When it happens, does Explorer crash (process exits), freeze (Not Responding), or does something else happen (BSOD, black screen, GUI overlay)? Can you open Task Manager (Ctrl+Shift+Esc) when it’s stuck?

1. Open Folder Options -> View -> check “Always show icons, never thumbnails” and disable the Preview pane (View ribbon). Then try opening the folders that cause the issue. If that fixes it, thumbnails/preview handlers are likely the cause.
2. Try in Safe Mode (hold Shift while clicking Restart -> Troubleshoot -> Advanced -> Startup Settings -> restart -> choose Safe Mode). If the problem stops in Safe Mode it’s almost certainly a third‑party extension/driver/service.
3. Create a new local user account and log into it. Does the problem appear there? If not, the user profile or shell extensions are suspect.
4. When it freezes, press Ctrl+Shift+Esc. If explorer.exe is “Not Responding” try right-click -> Restart. Report whether that works.

• System file check:
  • sfc /scannow
• DISM health (may take a few minutes):
  • DISM /Online /Cleanup-Image /RestoreHealth
• Clear thumbnail & icon cache (close Explorer first):
  • del /f /q %localappdata%\Microsoft\Windows\Explorer\thumbcache_*.db
  • del /f /q %localappdata%\IconCache.db
  • then restart PC
• Disk check (schedule on reboot if prompted):
  • chkdsk C: /f

• Third‑party shell extension (context-menu/preview handlers) — common with image viewers, cloud sync tools, antivirus, or codecs.
• Corrupt thumbnail/preview cache.
• Faulty GPU driver or hardware acceleration interacting with Explorer’s preview/thumbnail code.
• Corrupt user profile or bad background service.

• Use ShellExView (NirSoft) to disable all non‑Microsoft shell extensions, reboot, then re-enable one-by-one to find the offender.
• Check Event Viewer → Windows Logs → Application and System around the time of a freeze for errors (Explorer.exe crashes, Application Error, or WER entries) and paste the event details or a screenshot. Also run Reliability Monitor (type “reliability” in Start) and share the recent events.
• Try a Clean Boot (msconfig -> Services -> hide Microsoft services -> disable rest) to rule out background software.

Short answer — I don’t have the video​

While you re‑upload — quick checks that usually find the cause​

• Disable thumbnails & the preview pane: File Explorer → View → Options → View → check “Always show icons, never thumbnails” and close the Preview pane. If that stops the problem it’s almost certainly a thumbnail/preview handler or codec issue. (This is a very common cause; see the shell‑extension/thumbnail troubleshooting threads.)
• Try Safe Mode. If the problem disappears there it’s a third‑party shell extension or service.
• If problem happens only in folders with videos (eg. MOV), that format’s thumbnail handler can crash Explorer — people have seen mfmp4srcsnk.dll / MOV thumbnail problems before. If so, switch to a non‑thumbnail view and convert or remove the offending files.

If you can’t re‑attach right now, tell me:​

1. Which folders trigger it (Pictures, Videos, OneDrive, external drive, all folders?).
2. Does Task Manager show explorer.exe as “Not Responding” when it happens? Can you restart Explorer (Ctrl+Shift+Esc → right‑click Explorer → Restart)?
3. Does it happen in a new local user account or in Safe Mode?

• Zip it and attach the .zip file (right‑click the .mp4 → Send to → Compressed (zipped) folder). Most forums accept .zip.
• Upload the MP4 to cloud storage (OneDrive / Google Drive / Dropbox), set the file to shareable (Anyone with the link) and paste the link in your post.
• Upload unlisted to YouTube (or Streamable) and paste the link — unlisted keeps it private.
• For short clips, convert to an animated GIF or WebM (smaller clips only) and attach the GIF/WebM if the forum accepts those.

• Make a smaller MP4:
  ffmpeg -i input.mp4 -c:v libx264 -crf 28 -preset slow -c:a aac -b:a 96k output_small.mp4
• Make a WebM (good quality + smaller than GIF):
  ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 -c:a libopus output.webm
• Make a decent GIF (short clip; needs palette for quality):
  ffmpeg -i input.mp4 -vf "fps=15,scale=640:-1:flags=lanczos,palettegen" -y palette.png
  ffmpeg -i input.mp4 -i palette.png -lavfi "fps=15,scale=640:-1:flags=lanczos [x]; [x][1:v] paletteuse" -y output.gif

• Use the post editor’s “Attach files” or drag‑and‑drop. If it fails, the forum likely blocks .mp4 by extension or size — in that case ZIP it or use a cloud link. If you want, upload to OneDrive/Google Drive and paste the link here (set sharing to Anyone with link or Unlisted), and I’ll watch the clip and tell you what’s happening.

• Temporarily disable thumbnails and the Preview pane in File Explorer (View → Options → View → check “Always show icons, never thumbnails”). If that stops the hangs it’s almost certainly a thumbnail/preview handler or codec problem (this is a common cause — especially with .MOV/iPhone files).
• If it only happens in Safe Mode the culprit is third‑party software. Use ShellExView to hide non‑Microsoft shell extensions (focus on Preview/Thumbnail handlers), disable non‑Microsoft entries, then re‑enable by halves to find the offender.
• Clear the thumbnail cache and restart Explorer, and check Event Viewer → Application/System for Explorer errors when the freeze happens.

• When it hangs, try Ctrl+Shift+Esc → right‑click Windows Explorer → Restart. If the whole machine is frozen and you must power‑cycle, skip to the crash-logging steps below. These quick restarts and checking Task Manager can narrow transient vs persistent faults.

1. Safe Mode test — reboot to Safe Mode and use Explorer for a while. If it stops hanging in Safe Mode the cause is almost certainly a third‑party shell extension, service or driver.
2. Turn off thumbnails & Preview pane — File Explorer → View → Options → View → check “Always show icons, never thumbnails” and close the Preview pane. If hangs stop, thumbnail/preview handlers or codecs are likely.
3. Shell extensions check — download ShellExView (NirSoft), Options → Hide All Microsoft Extensions, then disable non‑Microsoft Preview/Thumbnail/Context Menu handlers (binary‑search disable half/half) until you find the offender. Reboot or restart Explorer between tests.

• GPU driver: fully uninstall the AMD driver using DDU (in Safe Mode), then install a known stable driver (or let Windows use the Basic Display Adapter) — a bad GPU driver can hang the whole UI. If you have Intel integrated graphics, try disabling the AMD adapter in Device Manager to test with the iGPU.
• Run SFC and DISM (admin): sfc /scannow then DISM /Online /Cleanup-Image /RestoreHealth. You mentioned reinstalling already, but these are quick sanity checks.

• Event Viewer: After the next hang (or immediately after reboot), open Event Viewer → Windows Logs → Application and System and copy the top Error(s) around the hang time (especially any explorer.exe, Display, or WHEA events). Paste the full event text here.
• If you’re comfortable: capture an Explorer dump when it’s hung using Sysinternals procdump (run elevated): procdump -e -ma explorer.exe C:\temp\explorer.dmp — then power‑cycle (if needed) and upload the .dmp (zip it). That gives the exact DLL/thread stack causing the lock. I can interpret the dump.

1. Boot to Safe Mode — if hangs stop, run ShellExView in normal mode and disable third‑party handlers (focus on preview/thumbnail handlers).
2. If Safe Mode doesn’t help, use DDU to remove the AMD display driver, boot normally with Microsoft Basic Display Adapter, and test for a day.