If you are having issues with PDF document generation and getting an error like “Failed to load PDF document,” there are a number of things to check. In my case, it seems to be a dependency for a WordPress plugin that is incompatible with Redis. In my case, I just temporarily turned off Redis and restarted Nginx, and the .pdf file generated fine. Of course, this is not a permanent solution, but it for this instance it works. Soon, I will work on finding out why the issue persists when Redis is turned on.
However, there can be a couple of other things to check as well as Redis:
- Invalid URL or path to the PDF file
- The PDF file is corrupted or damaged
- Insufficient permissions to access the PDF file
- The file format is not supported by the PDF viewer
- The PDF viewer is outdated or not configured correctly
To resolve the issue, you can try the following steps:
- Check if the URL or path to the PDF file is correct and try accessing it directly.
- If the file is corrupt, try to repair or recover it.
- Ensure that you have sufficient permissions to access the file.
- Try opening the file with a different PDF viewer to see if it is a compatibility issue.
- If the issue persists, try updating or reinstalling the PDF viewer.