MS Excel - Workbook Security
We can apply security to the workbook by the concept of protection available in the Review Tab of ribbon. MS Excel's protection-related features fall into three categories.
Worksheet protection:Protecting a worksheet from being modified, or restricting the modifications to certain users
Workbook protection: Protecting a workbook from having sheets inserted or deleted, and also requiring the use of password to open the workbook
You may want to protect a worksheet for a variety of reasons. One reason is to prevent yourself or others from accidentally deleting formulas or other critical data. A common scenario is to protect a worksheet so that the data can be changed, but the formulas can’t be changed.
To protect a worksheet, choose Review » Changes group »Protect Sheet. Excel displays the Protect Sheet dialog box. Note that providing a password is optional. If you enter a password, that password will be required to unprotect the worksheet. You can selected various option in which the sheet should be protected.Suppose we checked Format Cells option then Excel will not allow to format cells.
When somebody tries format the cells he or she will get the error as below.To unprotect a protected sheet, choose Review » Changes group » Unprotect Sheet. If the sheet was protected with a password, you’re prompted to enter that password.
Protecting a Workbook
Excel provides three ways to protect a workbook.
Require a password to open the workbook.
Prevent users from adding sheets, deleting sheets, hiding sheets, and unhiding sheets.
Prevent users from changing the size or position of windows.
Requiring a password to open a workbook
Excel lets you save a workbook with a password. After doing so, whoever tries to open the workbook must enter the password.To add a password to a workbook, follow these steps.
Choose File » Info » Protect Workbook » Encrypt With Password.Excel displays the Encrypt Document dialog box.
Type a password and click OK.
Type the password again and click OK.
Save the workbook.
To remove a password from a workbook, repeat the same procedure. In Step 2, however, delete the existing password symbols.
Protecting workbook’s structure and Windows
To prevent others (or yourself) from performing certain actions in a workbook, you can protect the workbook’s structure and windows. When a workbook’s structure and windows is protected, the user may not Add a sheet, Delete a sheet, Hide a sheet, unhide a sheet,etc and may not allowed to change size or position of a workbook’s windows respectively.
To protect a worksheet’s structure and windows follow below steps
Choose Review » Changes group » Protect Workbook to display the Protect Workbook dialog box.
In the Protect Workbook dialog box, select the Structure check box and Windows check box.
(Optional) Enter a password.