Access controls, file level permissions, and EFS encryption can be used to keep unauthorized persons inside the organizations from gaining access to the files. But the best security strategy is a multilayered one, and the more layers there are, the better.
Even with network-level protections and the security mechanisms built into modern operating systems, it never hurts to have extra protections built into the applications, as well.
Microsoft Office has a number of data protection features that help to protect the confidentiality and integrity of files created with Microsoft Word, Excel, and PowerPoint. In this article, we'll look at:. The password protection in Office was often criticized because of the weakness of its encryption.
Although it used the RC4 stream cipher with a bit key, the initialization vector IV and same keystream were used to encrypt the document each time you did so. That meant a hacker could crack the password by comparing two versions of a password-protected file. No hacking skills? No problem. Several software products are marketed as "password recovery tools" for cracking Office passwords. For stronger protection, you can increase the key length to bits by editing the registry or using Group Policy.
This improves the security of password-protected files, especially when long, complex passwords are used. What if you need to share encrypted files with users who are still running older versions of Office? Users running Office XP or Office can open and read files encrypted with the Office programs if:. To encrypt a file with password protection in Word, Excel, or PowerPoint, start by clicking the Microsoft Office button at the top-left corner of the Office program window.
Enter a strong password at least eight characters, containing upper- and lowercase alpha characters, numbers, and symbols into the Password field, as shown in Figure B. Retype the same password when prompted to do so. You can save the file in either the Office format. If you attempt to save in the older format, you'll see a dialog box advising you that the XML formats provide stronger encryption and asking if you want to convert to the XML-based format to increase the security of the document, as shown in Figure C.
Now when you or anyone else tries to open the document, a dialog box will open, prompting for the password, as shown in Figure D. In addition to the file encryption password you can set on a document, Office allows you to set a file-sharing password. The encryption option is called the password to open , and the file-sharing password is called the password to modify.
To set a password to modify, you use the Tools in the Save As dialog box this is also another way to set a password to open. Just click the Office Logo button and select Save As.
Then, in the Save As dialog box, enter a name for the file, click the down arrow beside Tools, and select General Options, as shown in Figure E. Note that the file-sharing password does not encrypt the document and is not a security measure. The General Options dialog box also allows you to open the Macro Settings section of the Trust Center, which we'll discuss later in this article. Clicking the Protect Document button in the General Options dialog box enables restriction of formatting and editing which can also be done from the Protect Document selection on the Review tab of the Office ribbon.
Sometimes, you want to distribute a document to others but don't want them to make changes to the formatting -- or want to limit them to only certain types of editing such as inserting comments. You select and apply formatting and editing settings through the task pane shown in Figure G. This prevents others from changing the styles or applying direct formatting to the document. By default, none of these options is enabled.
If the document contains formatting or styles you have disallowed, you'll be asked if you want to remove them. If there are parts of the document you want others to be able to edit freely, you can designate those selections as unrestricted or you can allow only specified persons to change those parts of the document. This is done with the Exceptions option in the Formatting And Editing task pane. Select the block of the document where you want to permit editing and either select Everyone from the Exceptions list or click More Users and enter the user names of those who should be permitted to edit the selection.
With this feature, you can allow one person to edit one section of the document, another person to edit the next section, and so forth. For example, you might allow someone from the legal department to edit a section that deals with legal issues but prevent that person from editing the sections that deal with technical issues. Once you've set the restrictions and exceptions you want, click the Yes, Start Enforcing Protection button. Then, in the Start Enforcing Protection dialog box, shown in Figure I , choose the option to protect with a password only no encryption or with user authentication document is encrypted and Restricted Access is enabled.
Excel password removal in Microsoft Excel How to password protect folders and files in Windows 7, XP and vista. Excel viewer to open, print and copy data in xls files. How to password protect PDF documents? Conditional Formatting In Excel How to make a graph in Excel and Microsoft cannot retrieve forgotten passwords, so be sure that your password is especially memorable.
There are no restrictions on the passwords you use with regards to length, characters or numbers, but passwords are case-sensitive. Be cautious when sharing files or passwords with other users. You still run the risk of passwords them falling into the hands of unintended users. Remember that locking a file with a password does not necessarily protect your file from malicious intent.
You can always ask an expert in the Excel Tech Community or get support in the Answers community. Protect a workbook.
Protect a worksheet. Protection and security in Excel. Table of contents. Next: Linked data types. Warning: Microsoft cannot retrieve forgotten passwords, so be sure that your password is especially memorable. Need more help?
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