Adobe Acrobat 7 Professional - Manual (Page 338)

Encrypting Adobe PDF files using certificates
When you encrypt a PDF file using a certificate, you specify a list of recipients and define
the recipients' level of access to the file--for example, whether the recipients can edit,
copy, or print the file. You can also encrypt a document using security policies. (See
Encrypting Adobe PDF files using security policies .)
Encrypting a document for a list of recipients begins by including your digital ID in the
list, so that you later are able to open the document. You then select the digital ID
certificates for those who you want to be able to open the document. You can obtain these
certificates from your list of trusted identities, from files on disk, from an LDAP server, or
from the Windows Certificate Store if you use Windows. After you build a list of
recipients who have access to the file, you can apply restricted permissions on an
individual basis. (See
Getting digital ID information from other users .)
Note: You can also create a security policy that stores certificate settings for easy reuse.
(See
Creating user security policies .)
To encrypt a file and create a recipient list:
1. From the Secure menu on the Tasks toolbar, choose Secure > Show Security Settings For
This Document.
2. From the Security Method menu, choose Certificate Security.
3. Select which digital ID you want to use, and then click OK. (See
Using digital IDs and
certification methods .)
4. In the Restrict Opening And Editing To Certain Identities dialog box, do the following:
●
Create a recipient list for your encrypted file: Use the options at the top of the dialog box
to locate identities; then select an identity name, and click Add To Recipients List to move
that name to the Recipients list.
●
In the Recipients list, highlight the recipient or recipients for whom you wish to set levels
of access, and click Set Recipient Permissions. (See
Password security options .) You can
set different levels of access for different recipients. If you don't set permissions, the
recipients have full access by default.
●
Select Enable Plaintext Metadata if you want search engines to have access to the
document metadata, even though the document contents are encrypted.
●
From the Encryption Algorithm menu, choose 128-bit AES or 128-bit RC4. If you select
128-bit AES, Acrobat 7.0 or Adobe Reader 7.0 is required to open the document.
5. Click OK to implement your settings, and then click OK again. Save and close the
document.
When someone from your recipient list opens the PDF document, the security settings you
specified for that person are used.
To change the security settings for an encrypted document:
1. From the Tasks toolbar, choose Secure > Show Security Settings For This Document.
2. In the Security panel, choose Change Settings.
3. Do any of the following, and then click OK:
●
To check a recipient's trusted identity, select the recipient, and then choose Recipient
Details.
●
To remove recipients, select one or more recipients, and then choose Remove from List.
Do not remove your own certificate from this list, or you won't have access to the file
using that certificate.
●
To change recipients' permissions, select one or more recipients, and then choose Set
Recipient Permissions.
To remove security settings from a document:
1. From the toolbar, choose Secure > Remove Security For This Document.
2. If prompted, type the Permissions password. If you don't know the Permissions password,
contact the author of the document.