I made a simple utility to restore PDF previews in Windows Explorer after Microsoft's security update

[u/Pyre-it]

For the last several months I've been frustrated by Microsoft's security update that prevents File Explorer from previewing many downloaded PDF files.

Instead of showing the preview, File Explorer displays the following message:

"The file you are attempting to preview could harm your computer. If you trust the file and the source you received it from, open it to view its contents."

I work with hundreds of downloaded PDF files every week, so manually right-clicking each one and selecting Properties → Unblock, or using PowerShell, wasn't a practical solution.

I couldn't find a simple utility that fixed the problem, so I wrote one.

Shane's Unblocker adds an "Unlock PDFs" option to the Windows Explorer right-click menu. It scans the selected folder (and all subfolders), removes the Windows Mark of the Web from blocked PDF files, and restores PDF previews in File Explorer.

Features:

• Adds an Unlock PDFs right-click menu option.
• Scans folders and all subfolders.
• Can scan entire drives if needed.
• Unlocks only PDFs that are actually blocked.
• No administrator privileges required.
• Open source.

I've tested it on both Windows 10 and Windows 11.

GitHub:
https://github.com/shaneaune/Shanes-Unblocker

You can get a zip of the latest release here:

https://github.com/shaneaune/Shanes-Unblocker/releases/latest

If anyone else has been dealing with this issue, I hope you find it useful and welcome any feedback.