Fixes & Troubleshooting
3 min read
How to Fix Corrupted PDF Headers Before Merging
Corrupted downloads or incomplete email attachments can cause "%PDF- header missing" errors. Here is how to quickly repair the file stream before combining.
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Step-by-Step Instructions
1
Re-Download Source File
Ensure the file was not cut off during initial download.
2
Open and Re-Save in Browser
Open the file in Chrome or Safari, press Print, and save as a clean PDF.
3
Re-upload to Merger
The rebuilt document will now merge cleanly.
Pro Tips for Best Results
- Preview your output file before downloading.
- All processing runs 100% locally in your web browser memory.
- No files are uploaded to any server.
Frequently Asked Questions
Unstable internet connections during download often truncate the initial file magic bytes.
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