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ADOBE ACROBAT 8 STANDARD
User Guide
Restrict URLs and attachments in PDFs
Acrobat warns you any time you try to open a URL (web link) or a file attachment that uses a disallowed file type.
URLs and disallowed file types (for example, EXE) are potentially dangerous because they can transfer or run
programs, macros, or viruses that can damage your computer.
You can allow Acrobat to contact specific websites by adding those URLs to your list of allowed websites in the Trust
Manager preferences. Remove any URLs you no longer want to visit. To open file attachments in Acrobat, you must
respond to a prompt by indicating that you always allow files of that type. The attachment’s file type is then added to
a list stored in the registry. If you want to restrict a file type that you permitted in the past, you can reset this list to
its default settings in the Trust Manager preferences.
Trust Manager preferences
To open the Trust Manager preferences, choose Edit > Preferences (Windows) or Acrobat > Preferences (Mac OS),
and select Trust Manager on the left.
Allow Opening Of Non-PDF File Attachments With External Applications
When selected, allows file attachments to
start external applications when you open the files. You must have the external applications to open the files.
Restore Default List Of Allowed And Disallowed File Attachment Types
Removes saved settings you chose for
opening attachments. For example, if you chose to always open TMP attachments when prompted, TMP appears on
the list of allowed file attachment types. By clicking Restore, you remove TMP from the list.
Change Settings
When clicked, lets you specify the default behavior for accessing the Internet from PDFs. To
restrict access to only the URLs you specify, select Let Me Specify A List Of Allowed And Blocked Web Sites (the
default). To allow access to all URLs, select Allow All Web Sites. To restrict access with all URLs in PDFs, select Block
All Web Sites.
To specify a list of allowed and blocked websites, type each URL in the text box, and click Allow or Block. Then
specify the default behavior for Acrobat for websites that aren’t in the list.
Note:
If you open a protected PDF and a security warning dialog box prompts you to allow or block a URL, select
Remember My Action For This Site, and the URL is added to this list.
Allow External Content
Allows Acrobat to read data from stream objects in a PDF. Stream objects are URLs or file
specifications identified by flags, as specified in
PDF Reference Version Fifth Edition: Adobe Portable Document
Format Version 1.6
. Use this option if you’re a PDF developer who creates PDF files that contain streams, or if you
work with these types of files.
Removing sensitive content
Preparing PDFs for distribution
Before you distribute a PDF, you may want to examine the document for sensitive content or private information
that can trace the document to you. Such information may be hidden or not immediately apparent. For example, if
you created the PDF, the document metadata likely lists your name as the author.
You may also want to remove content that can inadvertently change and modify the document’s appearance.
JavaScripts, actions, and form fields are types of content that are subject to change. If your document doesn’t require
these items, remove them before you distribute the document. You can use the Examine Document command to find
and remove hidden content from a PDF.