This message is displayed if the timestamp signer's certificate expires before the current time. Signature is timestamped but the timestamp has expired - Acrobat and Reader validate a timestamp based on the current time.Signature is timestamped but the timestamp could not be verified - Timestamp verification requires obtaining the timestamp server's certificate to your list of trusted identities.Signature is timestamped - The signer used a Timestamp Server, and your settings indicate that you have a trust relationship with that timestamp server.Signature date/time are from the clock on the signer's computer - The time is based on the local time on the signer’s computer.Review the Validity Summary in the Signature Properties dialog box. For more information about the Signature and Timestamp, click Signature Properties.Ĥ.

The Signature Validation Status dialog boxģ.

Open the PDF containing the signature, then click the signature. For more information, see Set signature verification preferencesĢ. Set your signature verification preferences. You assess the validity of a Digital Signature and Timestamp by checking the Signature Properties.ġ. Steps to assess the validity of a digital signature: On opening a signed document in the application if the signature status shows as unknown or unverified, validate the signature manually to determine the problem and possible solution.

Digital signature in adobe