Complete Guide on Security in Excel

Microsoft has always tried its best to see that its software is reliable and secure enough. Integrity is one of the core principles of Computer security. Data integrity involves ensuring that data or information remains accurate and relevant to those whom it may concern. This can be achieved by restricting unauthorized editing of a worksheet and especially in cases where the information may be edited before reaching the intended receiver. For anyone to make edits in such a scenario, one would have to input a valid password. This is thus one of the key steps that Excel has taken to ensure data security. Some of the security mechanisms include:

Password security:

When creating a password, the following guidelines might help:

1. Avoid using your name, date/year of birth as passwords.

2. A strong password should be eight characters long or more.

3. Always include a combination of uppercase, lowercase, numbers, and Symbols.

4. Avoid disclosing your password even to friends unless when necessary. It is always good to create new passwords each time.

5. Do not forget, passwords are case sensitive.

Workbook security:

We can add a password to our workbook such that only those with a password can open, edit and save changes to a workbook. To add password protection onto a workbook:

NB: it is good to always have a backup copy of your Excel documents in a different before or when setting its password. Forgetting the password would mean you cannot open your document anymore. Also, note that this security feature only restricts others without a password from uncontrollably editing but does not guarantee maximum security against those with malicious intentions.

Protecting worksheet.

Protecting a worksheet does not necessarily mean restricting access by others.


1. Have a backup of your Original Excel document. You can copy and paste it into another file location before starting working on it.

2. Select the Review tab from Excel's Ribbon.

3. Under the changes group, select the protect sheet.

4. A Dialog that accepts a password pops up. Type in your password.

5. Confirm your password by re-typing the password in the second Dialog.

How to protect your workbook

Additional security for your worksheet:

1. Click the review tab again.

2. Select protect workbook. A protect structure and windows dialog appear.

3. Type in your password and check the structure option in the dialog.

4. Press the OK button.

5. Retype password to confirm.

Request password to Open workbook:

1. Open your workbook that we set some security features.

2. Navigate to the File tab.

3. Click on Save as an option and browse a location.

4. A Dialog with saving as options will be displayed.

5. Click on tools and select general options.

6. Insert and confirm your password in the two dialogs that will pop up. Your password should be strong but easy to remember.

7. Click save and select Yes to replace the document.

8. Close the workbook.

9. Open the secured workbook, note that you must enter the password to proceed. If you forget your password it can be a bit challenging when it comes to opening your Excel document. A backup would do wonders at such a time.