Password Protecting and Encrypting MS Excel Files (Mac)

To password protect and/or encrypt a document using Microsoft Excel for Mac:

1. Open the MS Excel for Mac file you want to encrypt and password protect.

2. Select File > Passwords. The File Passwords window opens.

Locate passwords option from File menu

3. In the Password to open field, type a password. Passwords are case-sensitive.

Window to set password for opening or modifying the file

4. Click OK. You are prompted to reenter the same password.

5. Reenter the same password.

6. Click OK. The file is now encrypted and requires this password to open it.

7. Don't forget to save this password in a secure password manager and securely communicate this to any users or recipients of this file.

8. To reverse this, repeat the steps without entering a password. Save the document and it will no longer require a password to open it. 

NOTE:  Do not send an email with the file and the password in the same email. Find some other manner to communicate the password to users other than email if you will be emailing the file.