Sign For Free Help Center

Verification troubleshooting

Troubleshoot a failed verification

Identify the first failed or incomplete check, replace incorrect inputs, and rerun the verifier with the original completion files.

Role
Sender, Recipient, Signer, or document reviewer
Plan
Free and Basic
Platform
Modern web browser

Before you start

  • Use the completed PDF and audit_trail.pdf from the same completion email.
  • Keep the original attachments unchanged. Do not edit, optimize, print to PDF, or re-export them.
  • Save the current result JSON if another reviewer will need the exact failure details.

Diagnose the result

  1. Confirm the file order

    Place the signed PDF under Completed document (PDF) and audit_trail.pdf under Audit Trail (PDF). Add the unsigned source only under Original document (optional).

  2. Rerun with original attachments

    Download fresh copies from the same completion email, select Verify, and avoid files that were opened and resaved by another application.

  3. Read the first failed or skipped check

    Use the individual check cards to identify whether the problem involves the PDF hash, embedded audit evidence, page or field consistency, the optional original document, the cryptographic signature, or the public key.

  4. Correct the matching input problem

    Replace a wrong or modified file with the original attachment. If only the optional source-document check fails, select the exact unsigned PDF that the Sender originally uploaded.

  5. Resolve a missing public key carefully

    If the verifier shows Public key required, obtain the Base64 raw 32-byte Ed25519 public key from a trusted published source. Confirm that its fingerprint matches the displayed fingerprint, paste it, and select Use this key.

  6. Run the full check again

    Select Verify and review the overall result plus every individual check. Do not rely on the files while a required check remains failed or incomplete.

What happens next

If the original pair passes, preserve those unchanged files together. If a required check still fails, keep the files and result JSON, ask the Sender for a fresh completion email, and treat the document as unverified until the issue is resolved.

Warnings and limitations

  • A failed result does not by itself prove fraud. Wrong pairs, modified files, damaged downloads, missing public keys, and unsupported browsers can also prevent verification.
  • Do not remove a failing optional original document merely to hide that mismatch. Either use the correct source file or clearly record that the source-document check was not performed.
  • Use a manual public key only when it comes from a source you trust and its fingerprint matches the verifier's required fingerprint.
  • The verifier checks audit evidence without contacting the Sign For Free backend, but public-key lookup may contact a whitelisted external source.

Troubleshooting

No embedded audit payload was found
The Audit Trail field may contain the wrong PDF. Select the original audit_trail.pdf attachment.
The audit payload is invalid
The audit certificate may be corrupted or may not be a Sign For Free audit file. Ask the Sender for a fresh completion email.
A PDF SHA-256 or audit-evidence hash fails
The files may not belong together or one file's bytes may have changed. Use both original attachments from the same message.
Page count or field consistency fails
The completed PDF may have been altered or paired with the wrong certificate. Replace it with the original completed attachment.
The browser cannot run verification
Update the browser or try another current modern browser, then repeat the check with the same original files.

Still need help?

Preserve the two original attachments, the exported result JSON, the browser version, and the exact failed check, then ask the Sender for fresh completion files.