OJS 3.0.2 not loading pdfs

Our OJS instance has been having trouble recently as for some journals the pdfs will no longer load. When clicking on them it just takes the user to a blank page. This isn’t happening for all pdfs. Some journals will open the pdf in its own window and display it correctly. Others will download it and close the tab. I’ve checked the pdfs in the file storage as well as I was able to understand. The files were all in the submission folder (newer pdfs didn’t even have a public folder) and they all had the same owner:group and the same permissions.

I’ve noticed that the ones that have an issue will change the url from JOURNAL/article/view/ID to JOURNAL/article/download/ID.
I’ve also noticed that for the journals I’ve checked, the ones older than 2018 aren’t working and the newer ones are. I haven’t checked all journals, so this may be a red herring.

Working links:


Non-Working links:


Hi @califer,

Is anything showing up in the PHP error log related to this issue? Other users have reported similar issues with PDFs not displaying, so you may want to read through some older forum posts such as this one for solutions.

Also, OJS version 3.0 is no longer supported by PKP. I recommend that you upgrade to the newest version of OJS, as it is possible that your issue will be resolved by upgrading. However, other community members may wish to offer assistance.

Upgrading instructions are available in the PKP Administrator’s Guide.

Information about the latest version of OJS can be found on the PKP Website

All I’m seeing from the apache logs from the site is “ojs2: 404 Not Found”, but I can’t get it to trigger by going to the pdfs that won’t load, so I believe it to be unrelated. I’ve tried to upgrade it in the past but never had any success. I’ll look through the post you linked, thank you.