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Password Protecting PDF Files

To password protect a PDF file, simply go to File, Document Security:

When the Document Security window appears, select "Acrobat Standard Security."

When the Standard Security window appears, check the box for "Password Required to Open Document." Enter the User Password. Then check the box for "Password Required to Change Permissions and Passwords." Enter the Master Password.

Notes & Provisos
Password Selection:
Acrobat doesn't have any strict requirements for password selection. A common word, as you would find in the dictionary (dog, cat, rabbit, etc.) is a poor choice for a password. Such a password could be cracked in seconds with common hacker tools. Using WSU guidelines would be much better. Choose nonsense characters, with at least three of the four following types:

• UPPER CASE
• lower case
• Numbers (12345..)
• Symbols (*&^#%$)

Restrictions on copying, printing, etc.
Yes, this will prevent a cursory attempt. On a digital document, however, don't put too much trust in these features. There is typically a vulnerability that can be exploited.

To guard extremely sensitive data, always discuss with your systems administrator!

You can increase the encryption level from 40-bit to 128-bit, but your audience will need to have at least version 5 of Acrobat to read the file.

Note that you can also prevent people from printing the document, editing the document, copying or extracting content, and adding or changing comments and form fields.

When you have applied all the desired security settings, click "OK."

A window opens asking you to confirm the password to open the document.

After entering this and clicking OK, another window opens asking you to confirm the password to change security settings. Confirm the password. The Document Security window then opens. Click "Close."

The next time you try to open the document, Acrobat requires that you enter a password before the document is displayed.