Hi there,
Unfortunately we will need more information to diagnose this issue, could you please provide a video with the console open when you try to open a PDF?
Some possible solutions:
- CORS issue: Is there any CDN url for PDFJS express library
- Server/Client license key: Issues with message: "Origin does not match the domain set on license key"
- Load the lib folder from another domain: What is PDF.js Express? | Documentation
Best regards,
Kevin Kim