Operation Manual

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Electronic signatures
Last updated 4/7/2015
Set signature verification preferences
1 Open the Preferences dialog box.
2 Under Categories, select Signatures.
3 For Verification, click More.
4 To automatically validate all signatures in a PDF when you open the document, select Verify Signatures When The
Document Is Opened. This option is selected by default.
5 Select verification options as needed and click OK.
Verification Behavior
When Verifying
These options specify methods that determine which plug-in to choose when verifying a signature. The appropriate
plug-in is often selected automatically. Contact your system administrator about specific plug-in requirements for
validating signatures.
Require Certificate Revocation Checking To Succeed Whenever Possible ...
Checks certificates against a list of excluded certificates during validation. This option is selected by default. If you
deselect this option, the revocation status for approval signatures is ignored. The revocation status is always checked
for certifying signatures.
Verification Time
Verif y Signatures Using
Select an option to specify how to check the certificate-based signature for validity. By default, you can check the
time based on when the signature was created. Alternatively, check based on the current time or the time set by a
timestamp server when the document was signed.
Use Expired Timestamps
Uses the secure time provided by the timestamp or embedded in the signature, even if the signature’s certificate has
expired. This option is selected by default. Deselecting this option allows discarding of expired timestamps.
Verification Information Specifies whether to add verification information to the signed PDF. Default is to alert user
when verification information is too large.
Windows Integration specify whether to trust all root certificates in the Windows Certificates feature when
validating signatures and certified documents. Selecting these options can compromise security.
Note: It is not recommended to trust all root certificates in the Windows Certificate feature. Many certificates that are
distributed with Windows are designed for purposes other than establishing trusted identities.
Set the trust level of a certificate
In Acrobat or Reader, the signature of a certified or signed document is valid if you and the signer have a trust
relationship. The trust level of the certificate indicates the actions for which you trust the signer.