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Protecting Documents

[Reading Time - 1 minutes 59 seconds]


Do you have a document that you want to protect from attackers or nosy students?  You may want others to not open the document.  Or you may want them to be able to read the document but that's all.  Or you don't want them to be able to make changes to it, copy its content, or even print it.  What's the best way to do this?


Let's start with Microsoft Word. Word has the ability to encrypt the document so that nobody else can open it without the correct password. In Word click File then Protect Document and finally Encrypt With Password to create a password that is required to open the document. What if you want anyone to be able to open it but still restrict what they can do? In this case you can use the Word Restrict Editing features. In Word click File then Protect Document and then Restrict Editing. You can then limit formatting to a selection of styles or restrict the editing features to make the document read only, enter track changes, make comments, or fill in forms. After configuring these restrictions, you will again create a password (this is different from the Encrypt With Password) to protect the editing restrictions. And an Encrypt With Password is necessary to use Restrict Editing features.


But these Word options are not very detailed. For that reason, most users prefer to create a PDF document and then make restrictions on it, which allow for many more options. Many PDF readers (software that will display a PDF document), along with Adobe Acrobat, have the ability to create these restrictions.


Like Word, you can create a single password to open the document, or you can configure restrictions on the document (that requires another password). But the PDF restrictions are much more detailed that those with Word: for example, you can disable printing, copying to the clipboard, or restrict different types of editing on the document like highlighting or adding comments.


However, you will want to be sure to change the password security configuration in the PDF document to the highest level, which for many PDF readers is 256-bit AES. Some PDF readers will allow you to change the password security configuration setting to much weaker settings, but you shouldn't use these. Why? These lesser password security settings can easily be broken by the multitude of online PDF cracking sites (just do a web search for "PDF online cracking" and you'll see). Of course, be sure that you use a strong password along with the highest password security setting.


But what about PDF readers that are now part of most web browsers? Couldn't I just open the document in my web browser and print it out or copy its content to the Windows clipboard? No. The PDF readers in web browsers honor the restrictions that are set in the PDF document itself. If, for example, the PDF document restricts printing, opening it in a web browser may display the Print icon but clicking on it will do nothing.


However, if you have an unprotected PDF document that you want to extract specific pages, using the PDF reader in a web browser is a great tool. Just open the PDF document in the web browser, indicate which pages you want, and then select Print and finally the option to save to a PDF.