PDF password: How do I secure my file?

You can restrict access to a PDF by setting passwords and restricting certain features, such as printing and editing. However, you cannot prevent copies of a PDF file from being saved. Copies have the same restrictions as the original PDF.

There are two types of passwords:

1)  File Open Password.A document open password (also known as a user password) requires the user to enter a password to open the PDF.

2) Permissions Password. A permissions password (also known as a master password) requires a password to change permission settings. Using a permissions password, you can restrict printing, editing, and copying content in the PDF. Recipients do not need a password to open the document in Reader or Acrobat. They need a password to change the restrictions you have set. If the PDF is secured with both types of passwords, it can be opened with either password. However, only the password allows the user to change the restricted features. Because of the added security, setting both types of passwords is often useful and beneficial.

How to add a password to a PDF

• Open the PDF in Acrobat DC. Choose File > Protect Using Password. Alternatively, you can choose Tools > Protect > Protect Using Password. Choose whether you want to set a password for viewing or editing the PDF.
• Type and retype your password. The password strength appears next to your password to indicate whether the selected password is weak, medium, strong, or better. Click Apply. Acrobat displays a confirmation message that the file was successfully protected using the password.

 How to restrict the ability to edit a PDF

You can prevent users from changing PDF files. The Restrict Editing option prevents users from editing text, moving objects, or adding fields to a form. Users can still fill out form fields, sign, or add comments.

• Open the PDF in Acrobat DC and do one of the following: Choose File > Protect Using Password. Choose Tools > Protect > Protect Using Password. If prompted, click Yes to change the security. Choose Editing, and then type and retype your password. The password strength appears next to your password to indicate whether the selected password is weak, medium, or strong.
• Click Apply. Acrobat displays a confirmation message that the file was successfully protected using the password.

How to restrict printing, editing, and copying

You can prevent users from printing, editing, or copying content in a PDF. You can set restrictions that you want to apply to the PDF, which users cannot change unless you provide them with a password. Illustrator, Photoshop , or InDesign do not have viewing-only features. To open a restricted PDF in these applications, the user must enter the permissions password.

• Open the PDF in Acrobat DC and do one of the following:
• Select Tools > Protect > More Options > Encrypt with Password.
• Select File > Protect Using Password, and then select Advanced Password Protection from More Options.
• If you receive a prompt, click the “Yes” button to change the security.
• Select “Restrict Editing And Printing Of The Document”.

All Adobe products enforce password restrictions. However, if third-party products don't support these settings, document recipients may be able to bypass some or all of the restrictions you set.

• Type your password in the corresponding field. For each keystroke, the password strength meter evaluates your password and indicates the strength of the password.
• Select what the user can print from the “Printing Allowed” menu:
• None: Users are not allowed to print any documents.
• Low Resolution (150 dpi): Allows users to print at a resolution no higher than 150 dpi. Printing may be slower because each page is printed as a bitmap image. This option is available only if the Compatibility option is set to Acrobat 5 (PDF 1.4) or later.
• High Resolution: Allows users to print at any resolution, directing high-quality vector output to PostScript and other printers that support advanced high-quality printing capabilities.
• Select what the user can change from the “Changes Allowed” menu: None:
• Users are not allowed to make any changes to the document listed in the “Changes Allowed” menu, such as filling out form fields and adding comments.
• Insert, delete, and rotate pages: Allows users to insert, delete, and rotate pages as well as create bookmarks and thumbnails. This option is only available for high encryption (128 bit) RC4 or AES.
• Fill in form fields and sign existing signature fields: Allows users to fill out forms and add digital signatures. This option does not allow them to add comments or create form fields. This option is available only for high encryption (128 bit) RC4 or AES. Comment, fill in form fields, and sign existing signature fields: Allows users to add comments and digital signatures, and fill out forms. This option does not allow users to move page objects or create form fields.
• Anything but exporting pages: Users are allowed to edit the document, create and fill out form fields, and add comments and digital signatures.
• Choose any of the following options:

• Enable copying of text, images, and other content: Allows users to select and copy the contents of a PDF.
• Enable text access for screen readers for the visually impaired: Allows visually impaired users to read the document with screen readers, but does not allow users to copy or extract the contents of the document. This option is only available for high encryption (128-bit RC4 or AES).
• You select an Acrobat version from the Compatibility menu.
• You select a version that is equal to or lower than the recipients' version of Acrobat or Reader. The Compatibility option you select determines the type of encryption used. It is important to select a version that is compatible with the recipient's version of Acrobat or Reader.
• You choose what you want to encrypt:
• Encrypt all document contents: Encrypts the document and the document metadata. If this option is selected, search engines cannot access the document metadata.
• Encrypt all document contents except metadata. Encrypts the contents of a document, but still allows search engines to access the document's metadata.
• Encrypt attachments only: Requires a password to open file attachments. Users can open the document without a password. Use this option to create secure folders.

Click OK. At the prompt to confirm the password, retype the appropriate password in the box and click OK.

How to remove password security

You can remove security from an open PDF if you have the permissions to do so. If the PDF is secured with a server-based security policy, only the policy author or a server administrator can change it.

• Open the PDF, then select Tools > Protect > More Options > Remove Security.

Your options vary depending on the type of password security attached to the document:

• If the document only had a document open password, you click OK to remove it from the document.
• If the document had a permissions password, type it in the Enter Password box, and then click OK. Click OK again to confirm the action.