Can't Open PDFs with Preview — "Unidentified Developer" Error

abdomash wrote:

I'm encountering a frustrating issue with the Preview app when I try to open any PDF files. When I set Preview as the default program for PDFs, I keep getting the error message, "[File-name] cannot be opened because it is from an unidentified developer."

To open the file, I have to either:

Manually right-click it and select "Open With", then choose "Preview• "; OR

Navigate to the "Privacy & Security" settings and click on "Open Anyway• " EACH TIME I try to open the SAME file.

•

Funnily, when I click the ␣ space button while selecting the file, the preview of the file works properly. However, this is not very useful because the fullscreen doesn't work properly and not all features of Preview are available. Additionally, when I set other programs as the default PDF application (like Adobe Acrobat), this issue disappears, and the PDF files open directly without any problems.

I would like to use Preview normally as the default PDF file without having to fiddle through this trouble each time.

Device info:

MacBook Air M1, 2020

• macOS: 4.2.1 (23C71)

Compare your results with either—

Foxit Reader / Editor

https://www.foxit.com/

Wondershare PDFelement

https://pdf.wondershare.com/

The current stable release of Sonoma including bug fixes, security updates is macOS 14.3

Keep your Mac up to date - Apple Support

Keep your Mac up to date - Apple Support

You could try Adobe Acrobat Reader which is free. If you get the same result the files are definitely malformed in some way.