Summary
To prevent others from accessing sensitive data in your Excel files, protect your Excel file with a password.
Steps
1. Select File > Info.
2. Select the Protect Workbook box and choose Encrypt with Password.
3. Enter a password in the Password box, and then select OK.
4. Confirm the password in the Reenter Password box, and then select OK.
Warning:
1. Microsoft cannot retrieve forgotten passwords, so be sure that your password is especially memorable.
2. There are no restrictions on the passwords you use with regards to length, characters or numbers, but passwords are case-sensitive.
3. It’s not always secure to distribute password-protected files that contain sensitive information such as credit card numbers.
4. Be cautious when sharing files or passwords with other users. You still run the risk of passwords them falling into the hands of unintended users. Remember that locking a file with a password does not necessarily protect your file from malicious intent.
