Protection and security in Excel
- If you forget or lose your password, Microsoft can’t retrieve it for you.
- You should not assume that just because you protect a workbook or worksheet with a password that it is secure – you should always think twice before distributing Excel workbooks that could contain sensitive personal information like credit card numbers, Social Security Number, employee identification, to name a few.
- Worksheet level protection is not intended as a security feature. It simply prevents users from modifying locked cells within the worksheet.
- File-level: This refers to the ability to lock down your Excel file by specifying a password so that users can’t open or modify it. You have two choices here:
- File encryption: When you choose this option, you specify a password and lock the Excel file. This prevents other users from opening the file. For more information, see Protect an Excel file.
- Setting a password to open or modify a file: You specify a password to open or modify a file. Use this option when you need to give Read-only or edit access to different users. For more information, see Protect an Excel file.
- Mark as Final: Use this option if you want to mark your Excel file as the final version and want to prevent any further changes by other users. For more information, see Add or remove protection in your document, workbook, or presentation.
- Restrict Access: If your organization has permissions set up using Information Rights Management (IRM), you can apply any of the available IRM permissions to your document. For more information, see Add or remove protection in your document, workbook, or presentation.
- Digital signature: You can add digital signatures to your Excel file. For more information, see Add or remove a digital signature in Office files.
Note: To add a digital signature, you need a valid certificate from a certificate authority (CA).
- Workbook-level: You can lock the structure of your workbook by specifying a password. Locking the workbook structure prevents other users from adding, moving, deleting, hiding, and renaming worksheets. For more information on protecting workbooks, see Protect a workbook.
- Worksheet-level: With sheet protection, you can control how a user can work within worksheets. You can specify what exactly a user can do within a sheet, thereby making sure that none of the important data in your worksheet are affected. For example, you might want a user to only add rows and columns, or only sort and use AutoFilter. Once sheet protection is enabled, you can protect other elements such as cells, ranges, formulas, and ActiveX or Form controls. For more information on protecting worksheets, see Protect a worksheet.
Which level of protection should I use?
- To control the level of access users should have to an Excel file, use file-level protection. Let’s say you have a weekly status report of your team members in an Excel file. You don’t want anyone outside your team to be even able to open the file. There are two options available:
- If you don’t want others to open your file: You can encrypt the Excel file, which is the most common technique used. This basically means you lock it with a password and nobody except you can open it.
- If you want to enable Read-only or editing access to different users: Maybe, you want the managers in your team to be able to edit the weekly status report, but team members should only have Read-only access. You can protect the Excel file by specifying two passwords: one to open, and the other to modify. You can later share the appropriate passwords with the team depending on the access they should be given.
- To control how users should work with worksheets inside a your workbook’s structure, use workbook-level protection. Let’s say your status report workbook has multiple worksheets, and each worksheet is named after a team member. You want to make sure each team member can add data to their own worksheet, but not be able to modify any of the worksheets in the workbook, whether it be adding a new worksheet, or moving worksheets around within the workbook.
- To control how users should work within an individual worksheet, use worksheet-level protection. Let’s say each worksheet in your status report workbook contains data that is common to all worksheets, like header rows or a specific report layout, and you really don’t want anyone to change it. By protecting your worksheet, you can specify that users can only perform specific functions in a sheet. For example, you can give users the ability to enter data, but keep them from deleting rows or columns, or only insert hyperlinks or sort data.
You can use one or more levels of protection for your Excel data depending on your/your organization’s needs. You can choose to use all of the available options or a combination of options—it’s completely up to the level of security you want for your Excel data. For example, you may choose to encrypt a shared Excel file, as well as enable workbook and worksheet protection, while only using worksheet protection on a personal workbook just so you don’t accidentally delete any formulas