⚠️ PDF Signature Problem

PDF Signature Invalid After Email?
Here's Why It Happens

Email systems are breaking your PDF signatures through MIME encoding, server compression, and certificate chain disruption. Learn why traditional fixes fail and discover the email-proof solution.

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Why Email Attachments Break PDF Signatures

If you're seeing these error messages, you're experiencing a widespread problem that affects millions of PDF users.

⚠️

Common Error Messages

  • "At least one signature is invalid"
  • "The document has been altered or corrupted since it was signed"
  • "Signature has not yet been verified"
  • "Invalid policy constraint"
📧

Email Systems That Cause Problems

  • Gmail: Web-based viewer optimization
  • Outlook: Binary/ASCII detection issues
  • Yahoo Mail: Transport rule modifications
  • Corporate Systems: Security scanning

✅ You're Not Alone

This problem affects users across all email platforms and PDF viewers. It's not your fault - it's a fundamental flaw in how email systems handle PDF signatures.

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