FAQ

Last updated:July 8, 2026

This FAQ covers common questions about viewing certificates, importing certificates, and maintaining certificate validity, along with 4 glossary terms.

FAQ

How do I view certificate details?

  1. Open a PDF file and go to the Protect tab.
  2. Click Certificate Management to open the certificate list.
  3. Select the target certificate in the list.
  4. Click Details to view the full certificate information.

What should I do if a certificate has expired?

  1. Confirm that the certificate is past its validity period.
  2. Contact the certificate issuer to renew or replace the certificate.
  3. Import the updated certificate back into Certificate Management.
  4. Remove the old certificate if it is no longer needed.

How do I import a certificate sent by someone else?

  1. Save the certificate file to your local device.
  2. Open Certificate Management and click Add.
  3. Select the certificate file you received.
  4. Complete the import prompts and confirm that the certificate appears in the list.

Why can’t I use a certificate after importing it?

  1. Check whether the file format is .pfx, .p12, or .cer.
  2. Check whether the certificate password was entered correctly.
  3. Confirm that the certificate is still valid and suitable for the current signing or encryption task.
  4. If needed, delete the certificate and import the correct one again.

Glossary

TermDefinition
Signature certificateA certificate used to digitally sign a PDF file so the signer identity and document integrity can be checked.
Encryption certificateA certificate used to encrypt a PDF file and help restrict unauthorized access.
Trusted certificateA certificate recognized as trusted in the current environment and commonly used for validation or trust relationships.
Certificate passwordA protection password required when importing some certificate files.