How to Put a Password in My File in Excel

1. Launch Excel.
2. Click the 'File' menu option, then click 'Info.'
3. Click the 'Protect Document' icon and select 'Encrypt With Password.' A window pops up and prompts you to enter a password.
4. Type a password into the box. Mix upper- and lowercase letters with numerals and special characters -- such as question marks and dollar signs -- to improve the strength of the password. Excel allows up to 255 characters in a password.
5. Click 'OK' to input the new password. Save the file normally to lock in the encryption.