PDF acting up? These are the most common problems our readers encounter — and how to fix them in under two minutes.
Cause: Incomplete download, browser crash during save, or corrupted email attachment.
Fix: Re-download the file. If the problem persists, try opening it in a different reader (Edge, Chrome, or Preview). Some readers are more tolerant of minor corruption than others. Desktop editors like PDF Agile include a built-in repair tool.
Cause: The PDF uses a font not installed on your system, or the font was not embedded when the file was created.
Fix: Open the PDF in the same program that created it (e.g., Word, InDesign). If you only have the PDF, use a desktop editor to substitute the missing font, or ask the sender to re-export with "Embed Fonts" enabled. See how to edit fonts in PDF.
Cause: High-resolution images, unoptimised scans, or embedded multimedia.
Fix: Use a PDF compression tool. See our Compress PDF guide for step-by-step instructions. For scans, reducing DPI from 300 to 150 cuts file size by ~75% with minimal quality loss for screen viewing.
Cause: Corrupted font cache, outdated printer driver, or the PDF uses a color space your printer does not support.
Fix: Try "Print as Image" in the Advanced print settings. This renders each page as a flat image, bypassing font and color-space issues. See our Fix PDF Printing Issues guide for more solutions.
Cause: The PDF is a flat scan (not a true form), or the form has security restrictions.
Fix: If it is a scan, run OCR first to make it editable. If it has security, use an unlock tool. See How to Edit PDF Forms and How to Unlock PDF.
If your problem is not listed here, browse our full list of 90+ tutorials or submit a tutorial request and we will create a guide specifically for your issue.