Microsoft PowerPoint file encryption allows you to quickly and easily secure PowerPoint presentations. Though early versions of Office’s file encryption were notoriously weak, newer versions are much stronger. Microsoft Office 2007-2010 offers AES-128 encryption using the SHA-1 algorithm, while Office 2013 uses AES-128 and SHA-512. The use of SHA-512 is a major upgrade over SHA-1 in preventing brute-force attacks against passwords.
Unlike the Office Suite for Windows, the Mac versions of Excel, PowerPoint, and Word have slightly different interfaces. Encrypting a PowerPoint presentation on Mac is different enough from encrypting a Word document that I chose to cover the two separately.
Microsoft PowerPoint File Encryption
To encrypt a document, open Microsoft PowerPoint. Click on the File menu, and from the drop-down select “Passwords”.
A new dialogue will appear. If you wish to encrypt the document, check the “Encrypt this presentation…” box. Immediately a password prompt will appear. Unlike Microsoft Word for Mac, I have found no meaningful limit on password length with Microsoft PowerPoint file encryption. I have successfully used passwords as long as 60 characters. When you have entered your password, click “Set Password”.
The “Password to modify” prevents the presentation from being modified without the correct password. Like the password to open the document, I have not found a length limitation for this password.
Microsoft PowerPoint file encryption is an excellent, user-friendly tool for protecting sensitive files. If you have extremely sensitive presentations you may wish to further protect them behind full disk encryption or volume level encryption.
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