# [Preferences] dialog box

This dialog box appears when you select [Preferences] from [Digital Certificate] of the [Document] menu in Viewer.
Use this dialog box to set up Digital Certificate.
Important
If you started several Viewer and then set up the operation environment of one among them, note that its settings will be applied to others.

### [Trustworthy level of Certificate]

Select the trustworthy level of a certificate. The default is [Middle].
When signing a document, setting up security, and verifying the signature of a document, the contents of validity verification depend upon each trustworthy level as follows.
(1) The signature of the certificate is valid.
(2) The certificate can chain to its root certificate.
(3) The certificate is within its valid date.
(4) The purpose of using the certificate is valid.
(5) Revocation of certificate can be confirmed.
(The CRL can be found, and its signature and expiration date are valid.)
(6) The certificate is not revoked.
(It is not registered in its CRL)

- [High]
  Confirms the revocation of a certificate.

- In signing a document or setting up security, if you succeeded in verifying a certificate (1) - (6), you can use the certificate.
- In verifying the signature of a document, if you succeeded completely in verifying a certificate (1) - (6), the verification status of the signature will be "Trustworthy".
- In signing a document or setting up security, if you failed in verifying any one of the above (1) - (6), you cannot use the certificate.
- In verifying the signature of a document, if you failed in verifying any one of the above (1) - (6), the verification status of the signature will be "Invalid".

- [Middle]
  Confirms the revocation of a certificate.

- In signing a document or setting up security, if you failed in verifying (5) (you cannot confirm the revocation of the certificate), but you succeeded in verifying (1) - (4), you can use the certificate.
- In verifying the signature of a document, if you succeeded completely in verifying a certificate (1) - (6), the verification status of the signature will be "Trustworthy".
- In verifying the signature of a document, if you failed in verifying (5) (you cannot confirm the revocation of the certificate), but you succeeded in verifying (1) - (4), the verification status of the signature will not be "Trustworthy".
- In signing a document or setting up security, if you failed in verifying any one of (1) - (4), (6), you cannot use the certificate.
- In verifying the signature of a document, if you failed in verifying any one of the above (1) - (4), (6), the verification status of the signature will be "Invalid".

- [Low]
  Does not confirm the revocation of a certificate.

- In signing a document or setting up security, if you succeeded in verifying (1) - (4), you can use the certificate.
- In verifying the signature of a document, if you succeeded in verifying (1) - (4), the verification status of the signature will be "Trustworthy".
- In signing a document or setting up security, if you failed in verifying any one of the above (1) - (4), you cannot use the certificate.
- In verifying the signature of a document, if you failed in verifying any one of (1) - (4), the verification status of the signature will be "Invalid".

### [Revocation checking of Certificate]

#### [Confirm revocation online]

Set up how to confirm the revocation of a certificate.
By default, this box is cleared. If [Trustworthy level of Certificate] is [Low], you cannot select this check box.
If you select the box, CRL described in the "CRL Distribution Point" for the certificate will be checked via network. The network settings need to be configured on the [Connect] tab in the [Internet Options] dialog box, which can be launched from the Windows Control Panel.
If this box is cleared, you cannot confirm CRL via a network.

### [Signature]

#### [Write signature as per contents of setup]

When you sign a document, use the signature specified before. When you select [Digital Certificate] in the [Signature Module Options] dialog box, you can sign a document by clicking the signing point of a page without displaying the [Signature Settings] dialog box.
By default, this box is cleared.

#### [Register the verified Certificate]

Once you verify the signature of a document, the certificate that was used for the signature is registered with [Other People] in the Windows Certificate Manager. If verification status is "Validity Unknown" or "Invalid", the certificate is not registered. Certificates registered in the [Other People] of Windows Certificates can be used when setting security by Digital Certificate.
By default, this box is cleared.

#### [Signature Settings]

Displays the [Signature Settings] dialog box to set up a signature. The signature setting is saved, and it is referred to when signing a document.

### [Security]

#### [Default target of search]

Specify the default for [Target of search] in the [Add Certificate] dialog box.
You can select [Remote search] after executing [Remote Settings] and configuring the LDAP server that is a target of the search.

#### [Remote Settings]

The [Remote Settings] dialog box appears. Configure the LDAP server that is a target of the search.