PDF Preview deactivated with Windows update

The problem for me was that ALL extensions - TXT, PDF, JPG, DOC and XLS, all of which used to work before I left for a 6-month vacation, were broken,  I left in October. I tried every one of these prescriptions without a remedy. Nothing worked. Finally, I went back to an image I had made in September 2025 and locked down all further Windows updates. Works like a dream now. Wasted enough time.

The idiots at Microsoft should give those who know what they are doing the option to turn the annoying, bloody thing off. This one-size-fits-all crap makes me want to go to a Mac, but that is too drastic! I don’t need Microsoft babysitting me and dictating to me what I can or cannot do. Give us the option and the credit for half a brain!

My gosh, thank you!

This worked for me. 

4. Advanced: Fix for "Downloaded" or "Blocked" Files 

Recent Windows security updates (starting late 2025) may block previews for files downloaded from the internet. 

• Unblock a file: Right-click the PDF > Properties. In the General tab, look for a "Security" section at the bottom and check Unblock.
• Trusted Sites: For files on secondary or network drives, go to Internet Options > Security > Local Intranet > Sites > Advanced and add the drive path (e.g., D:\

Step 1: Unblock all already downloaded PDF files.
Open PowerShell as Administrator and run:

Unblock-File -Path "C:\Users\admin\Downloads\*.pdf"

Replace adminwith the actual path where your files are downloaded. This would be your device name. you can find this by right clicking on "this pc" (my computer), or and going to properties. then scroll down till you see device name or typing device name in search on the start bar.
Usually, it's your user folder on drive C. You can check your exact user path by running this command in PowerShell:

The solution that Randy Hagen provided was the first step in fixing the issue for me.

The second thing I did that solved the problem was adding trusted sites
(see the link below for instructions on how to do this).

Simply copy the path from where your PDF files are located in Windows Explorer, and paste it after "file://" when adding a trusted site.

https://docs.konnekt.io/troubleshooting/pdf-preview-broken-after-windows-11-update

Hope this helps anyone who hasn’t gotten their previews working yet!

Thank you for the suggestions, I just tried the repaired and nothing changed. I check and my preview handeler is enable...

Hello, as mentioned in previous posts, this issue is not related to any Adobe application. It is caused by a recent Windows update (KB5066835).

The update introduced a change that blocks previewing of all files originating from the internet. In the registry (RegEdit), the value URLACTION_SHELL_PREVIEW (0x180f) in the Internet Zone (Zone 3) was modified from Enabled (0) to Disable (3). It is technically possible to revert this value to 0 manually, but doing so reduces the security level of the device as the change was probably intentional to prevent certain threats.

I have the same problem, i have started using Adobe Bridge, and you can set filters just for PDFs, rename and preview at the same time

Hi there we are having the same issues it's a total nightmare we spend 90% of our time renaming PDF files via the preview panel.  My IT guy is looking into it but doesn't sound as though it's a straightforward fix.  As it's really holding us up I've been trying to figure a way around it.  So, if you open a PDF and then ATTACH all of the files you need to access in the attachment panel, THEN save the attachments into a different folder temporarily - they are then visible on the preview panel and can be moved back into the original folder  and let them over-write.  Not ideal but is a solution that's helping us get on for now.  Hope of some help.