MobileRead Forums - View Single Post - PDF's no longer work after import into Calibre?

Cyber-Wizard · Today, 06:59 AM

Calibre Version: 8.15
OS: Windows 11 Pro 25H2

Recently I've noticed that, after I import some PDF's into Calibre, the PDF can no longer be opened.
I don't generally test books after importing them into Calibre as I understood that Calibre doesn't do anything to PDF's on adding them, they just get copied into a library folder.

Over the last week I have opened up three PDF's after adding them to Calibre and upon opening them I get an error stating that the PDF document is invalid.
I have been using PDF Studio Viewer for some time now and I tried switching my default viewer to Chrome but still get an error.

I can open up the original PDF in both applications without any issues.
If I try to open up the PDF directly from the folder where Calibre stores it after adding I still get an error.
If feels not so much as something that Calibre does when allowing the document to open in my default PDF viewer as it's something that has happened to the PDF when Calibre copies it to the library folder.

I don't usually open them after adding so I'm not certain how long this has been happening.
It also doesn't happen with every PDF. Out of 5 that I added today, only two failed to open after they were added to Calibre.

Has anyone encountered this and perhaps found a fix?

Today, 06:59 AM	#1
Cyber-Wizard Junior Member Posts: 4 Karma: 10 Join Date: Nov 2025 Device: Rakuten Kobo Aura	PDF's no longer work after import into Calibre? Calibre Version: 8.15 OS: Windows 11 Pro 25H2 Recently I've noticed that, after I import some PDF's into Calibre, the PDF can no longer be opened. I don't generally test books after importing them into Calibre as I understood that Calibre doesn't do anything to PDF's on adding them, they just get copied into a library folder. Over the last week I have opened up three PDF's after adding them to Calibre and upon opening them I get an error stating that the PDF document is invalid. I have been using PDF Studio Viewer for some time now and I tried switching my default viewer to Chrome but still get an error. I can open up the original PDF in both applications without any issues. If I try to open up the PDF directly from the folder where Calibre stores it after adding I still get an error. If feels not so much as something that Calibre does when allowing the document to open in my default PDF viewer as it's something that has happened to the PDF when Calibre copies it to the library folder. I don't usually open them after adding so I'm not certain how long this has been happening. It also doesn't happen with every PDF. Out of 5 that I added today, only two failed to open after they were added to Calibre. Has anyone encountered this and perhaps found a fix?