According to the description on the official website, you don't need a password to open the file as it will open in Read-Only mode.
Quote from the website: "The file will ask for a password. No password shall be entered. Just open the file as read only. This feature is kept intentionally to safeguard the calculation functions and other important data which is important for correct result and is not required by a user."
To find more about it, use the following link: http://astrostudents.tripod.com/varshphal.html
