Editor's notation: In the video, Brandon Vigliarolo walks you through the steps of securing an Excel workbook with a countersign in Microsoft Office 365 . The steps are similar to what Susan Harkins describes in this tutorial, which was start published in January 2011 and updated in March 2019.

Securing data is a tiered process with countersign protection at the bottom level–the file level. It's a offset pace attempt, but certainly not the only step you should take to protect confidential and proprietary data. Countersign protecting an Excel workbook at the file level controls access in two ways: It lets a user in, and it lets a user salvage changes. In this commodity, I'll evidence you lot more than simply how to countersign-protect a workbook. You lot'll learn what that protection does and doesn't practice for y'all and how to avoid some gotchas.

I'm using Part 365 Excel (desktop), but you can user before versions. There's no demonstration file–you won't need 1. Y'all can't add together a password to a file open in the browser, nor can you open it in the browser.

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Security v. protection

Earlier we talk over Excel's password-protection characteristic, let'south clarify what nosotros hateful by security. Although the terms security and protection are bantered nearly interchangeably, characteristic-wise in Excel, they aren't the same thing. Security lets you choose who gets in and by virtue of doing so, who doesn't. Protection limits users who are already in. Security is nigh access; protection is about maintaining integrity.

Assign the countersign

The starting time step is to assign a password. Y'all can piece of work with whatsoever file, but for our purposes, I suggest a blank workbook instead of an important working file, just in case. To assign a password to an Excel workbook, do the following.

  1. From the File carte, choose Save As. In Excel 2007, click the Function button and choose Save Equally.
  2. Under the name and type controls, click More options. (If you've suppressed the Backstage area, y'all'll skip this stride.)
  3. In the resulting Save Equally dialog, click the Tools dropdown (to the left of the Relieve button) and choose General Options.
  4. In the resulting dialog (Figure A) you tin set two passwords: I to open up the workbook and ane to change the workbook. Avant-garde options allow you set encryption options.
  5. Enter one or both passwords and click OK.
  6. Ostend the countersign(s) and click OK.
  7. Click Save.

Be certain to note the password somewhere condom, but in case you forget it.

Figure A

Enter the password and note it in a secure identify.

Setting a password to open the workbook is self-explanatory; if a user doesn't know the password, he or she can't open the file. That gives you a great bargain of control if yous practise a reasonable job of securing passwords. Of course, you tin't actually do annihilation well-nigh the user who shares a password, just that's an birthday different problem. Just remember that this password only keeps users out; a user that knows this password has access to all the data and can modify the data once in.

SEE: Cost comparison calculator: G Suite vs. Office 365 (Tech Pro Research)

That'southward where the 2d password comes in; past assigning this password, yous allow users to open up the workbook and view the information while withholding permission to modify annihilation. A user who knows this password tin can view and modify data and also save changes to the workbook.

A user who doesn't know the second password can open up and view the information past clicking the Read Only selection, only information technology's Read-Only–sort of. This user tin still modify data, but the password-protected workbook won't let the user save changes–sort of. Hither'south the bargain: A user without the modifying password can even so view, alter, and relieve changes, if the user can go far. This user just can't save the changes to the protected workbook. The user can, however, salve the protected workbook using a new proper noun, which certainly circumvents the process.

SEE: A winning strategy for cybersecurity (ZDNet special report) | Download the written report as a PDF (TechRepublic)

Important considerations

Before yous start password protecting all your workbooks, at that place are three important things to proceed in mind:

  • Anyone with the password to change the workbook tin as well remove the password protection. Use this detail option wisely; be careful who you give the password to.
  • Casual users won't have the expertise to fissure your password, just everyone can buy password-cracking software. Your best protection against this type of tampering (or outright theft) is to assign a ridiculously long password of random characters. Doing so won't defeat specialized software, just it will slow it downwards and that filibuster might crusade the would-be cracker to put your workbook bated. On the other manus, information technology'due south certain to annoy your users. Balancing the two needs tin be a bit of a high-wire human activity. For more on this subject, read Stiff passwords–realistic or burdensome.
  • If you forget your password, you tin't get into your workbook and brand changes, just y'all tin buy the countersign-cracking software.

Excel's password protection is a great feature and fortunately, it's easy to implement. Just don't misfile it with sheet protection and past all means, don't rely solely on information technology to secure sensitive data.

Run into: ten Excel fourth dimension-savers you might non know about (free PDF download) (TechRepublic)

Ship me your question nearly Office

I answer readers' questions when I tin can, but there'due south no guarantee. Don't send files unless requested; initial requests for help that make it with fastened files will be deleted unread. You can send screenshots of your data to help clarify your question. When contacting me, be as specific as possible. For example, "Delight troubleshoot my workbook and fix what's wrong" probably won't get a response, simply "Tin can you tell me why this formula isn't returning the expected results?" might. Please mention the app and version that y'all're using. I'm not reimbursed by TechRepublic for my time or expertise when helping readers, nor do I ask for a fee from readers I help. You lot tin contact me at susansalesharkins@gmail.com.