Why some PDFs cannot be opened

A PDF can fail because it is encrypted, damaged, unusually complex or uses a feature that the browser library does not support. The error does not mean the original file is lost.

Check for encryption

Password-protected PDFs cannot be opened by this browser tool. Use a trusted PDF application to export an unprotected copy only when you are authorized to do so.

Try a fresh copy

Download the file again or ask the sender to re-export it. An incomplete download can look like a broken PDF.

Reduce complexity

Very large scans and documents with many high-resolution images can exceed available browser memory. Try a smaller section or a desktop browser.

Keep the source

Never delete the original until the output opens and contains the pages you expect.