Adobe Acrobat 8 3D - Manual (Page 272)

265 ADOBE ACROBAT 3D VERSION 8
User Guide
See also
“Secure PDFs using policies” on page 273
Add a password and security
1 Click the Secure button in the Tasks toolbar, and choose Password Encrypt.
2 Click Yes to the prompt about changing the security, and if necessary, type the Permissions password that lets you
change security settings. If you don’t know the password, contact the author of the PDF.
3 In the Password Security - Settings dialog box, set the security options as desired, confirm the password, click OK,
and then click OK again.
4 Save the document to apply the security settings.
Note: You can also restrict editing capabilities when you certify a document, or when you apply a policy to a PDF.
Remove passwords and security settings
You can remove passwords and security policies from an open PDF if you have the permissions to do so. If the PDF
is secured with a security policy that resides on a server, the changes can be made only by the author of the policy or
by a server administrator.
1 Do one of the following:
• Click the Secure button in the Tasks toolbar, and choose Remove Security. Type your password, and click Yes
to the prompt about removing the security.
• In the Security tab of the Document Properties dialog box, choose No Security from the Security Method menu.
2 When prompted, specify the Permissions password, and then click OK.
Security options
You can set the following options when you create a PDF or when you apply password protection to a PDF. Options
vary depending on the Compatibility setting. Security options are not available for PDF/X standards or presets.
Compatibility Sets the type of encryption for opening a password-protected document. The Acrobat 3 And Later
option uses a low encryption level (40-bit RC4), while the other options use a high encryption level (128-bit RC4 or
AES). Acrobat 6 And Later lets you enable metadata for searching.
Be aware that anyone using an earlier version of Acrobat cannot open a PDF document with a higher compatibility
setting. For example, if you select the Acrobat 7 And Later option, the document cannot be opened in Acrobat 6.0
or earlier.
Encrypt All Document Contents Select this option to encrypt the document and the document metadata. If this
option is selected, search engines cannot access the document metadata.
Encrypt All Document Contents Except Metadata Select this option to encrypt the contents of a document but still
allow search engines access to the document metadata.
Encrypt Only File Attachments Select this option to require a password for opening file attachments. However, users
can open the document without a password.
Require A Password To Open The Document Select this option to require users to type the password you specify to
open the document. This option is unavailable if Encrypt Only File Attachments is selected.
Document Open Password Specify the password that users must type to open the PDF file.