Microsoft Excel 2010 : Collaborating with Colleagues - Protecting Workbooks and Worksheets

Excel gives you the ability to share your workbooks over the Web, over a corporate intranet, or by copying files for other users to take on business trips. An important part of sharing files, however, is ensuring that only those users you want to have access to the files can open or modify them. For example, Consolidated Messenger might have a series of computers available in a processing center so supervisors can look up package volumes and handling efficiency information. Although those computers are vital tools for managing the business process, it doesn’t help the company to have unauthorized personnel, even those with good intentions, accessing critical workbooks.

You can limit access to your workbooks or elements within workbooks by setting passwords. When you set a password for an Excel workbook, any users who want to access the protected workbook must enter the workbook’s password in a dialog box that opens when they try to open the file. If users don’t know the password, they cannot open the workbook.

To set a password for a workbook, open the workbook to be protected, and click the File tab to display the workbook in the Backstage view. Then, on the Info page of the Backstage view, click the Protect Workbook button and then click Encrypt With Password. The Encrypt Document dialog box opens, with a Password box in which you can type your password. After you click OK, the Confirm Password dialog box opens, in which you can verify the password required to open the workbook. After you have confirmed the password, click OK. Now the Info page of the Backstage view indicates that users must enter a password to open the file.

To remove the passwords from a workbook, repeat these steps, but delete the passwords from the Encrypt Document dialog box and save the file.

If you want to allow anyone to open a workbook but want to prevent unauthorized users from editing a worksheet, you can protect a worksheet by displaying that worksheet, clicking the Review tab and then, in the Changes group, clicking Protect Sheet to open the Protect Sheet dialog box.

In the Protect Sheet dialog box, you select the Protect Worksheet And Contents Of Locked Cells check box to protect the sheet. You can also set a password that a user must type in before protection can be turned off again and choose which elements of the worksheet a user can change while protection is turned on. To enable a user to change a worksheet element without entering the password, select the check box next to that element’s name.

The check box at the top of the worksheet mentions locked cells. A locked cell is a cell that can’t be changed when worksheet protection is turned on. You can lock or unlock a cell by right-clicking the cell and clicking Format Cells on the shortcut menu that appears. In the Format Cells dialog box, you click the Protection tab and select the Locked check box.

When worksheet protection is turned on, selecting the Locked check box prevents unauthorized users from changing the contents or formatting of the locked cell, whereas selecting the Hidden check box hides the formulas in the cell. You might want to hide the formula in a cell if you draw sensitive data, such as customer contact information, from another workbook and don’t want casual users to see the name of the workbook in a formula.

Finally, you can password-protect a cell range. For example, you might want to let users enter values in most worksheet cells but also want to protect the cells with formulas that perform calculations based on those values. To password-protect a range of cells, select the cells to protect, click the Review tab and then, in the Changes group, click Allow Users To Edit Ranges. The Allow Users To Edit Ranges dialog box opens.

To create a protected range, click the New button to display the New Range dialog box. Type a name for the range in the Title box, and then type a password in the Range Password box. When you click OK, Excel asks you to confirm the password; after you do, click OK in the Confirm Password dialog box and again in the Allow Users To Edit Ranges dialog box to protect the range. Now, whenever users try to edit a cell in the protected range, they are prompted for a password.

In this exercise, you’ll password-protect a workbook, a worksheet, and a range of cells. You will also hide the formula in a cell.