A payroll list, a customer file, a contract: some documents shouldn't fall into just anyone's hands. Adding a password to an Excel file or a PDF is a simple and effective protection, integrated directly into Microsoft 365.

1. Put a password on an Excel file

Password encryption on an Excel file prevents it from being opened without the password. Here are the steps:

1. Open the workbook, then click File > Info.
2. Select Protect workbook > Encrypt with password.
3. Enter a password, click OK, then confirm it.
4. Save the file to apply the protection.

Important: Passwords are case-sensitive and can be up to 15 characters long. Microsoft cannot recover a forgotten password, so keep it safe.

2. Protecting a Word document

The process is the same in Word: File > Info > Protect Document > Encrypt with Password. The document becomes unreadable without the password.

3. Put a password on a PDF

You can create a protected PDF from Word or Excel:

1. Open the document, then File > Save As and choose the PDF.
2. Click on Options.
3. Check Encrypt the document with a password, then enter your password.

The generated PDF will ask for the password upon opening.

Choose a good password

A strong password is long, unique, and difficult to guess. For business use, a password manager prevents forgotten passwords and strengthens security for the entire team.

Frequently Asked Questions

Can I remove the password later?

Yes. Go back to File > Info > Protect, open the encryption box, delete the existing password and save the file again.

Does the password also protect against modification?

Encryption protects the file from being opened. To restrict only modifications, use the "Protect sheet" or "Restrict editing" options instead.

Secure your sensitive data

Need help protecting your data, both personally and professionally? Contact OKTO Solutions or discover our services.