I recently had to unlock Excel file password protected workbook that contained important reports. Unfortunately, nobody remembered the password, and most of the free methods I found online either didn't work or only removed worksheet protection.

After some research, I realized that unlocking an Excel file password protected with an opening password is completely different from removing sheet restrictions. If the workbook is encrypted, you'll need the correct password or a reliable recovery method.

While looking for solutions, I came across the SysTools Excel Password Recovery Tool. It seemed useful because it supports both unknown and partially known passwords, which can save a lot of time if you remember even a few characters.

Some features that stood out:

* Recover passwords from XLS and XLSX files
* Brute Force mode for unknown passwords
* Mask Attack for partially remembered passwords
* Supports all major Excel versions
* Keeps the original file unchanged
* Simple and easy-to-use interface

My advice is to first check for password hints, old emails, or backup copies. If that doesn't help, a password recovery tool can be a practical option to unlock an Excel file password protected with an unknown password.

Hopefully this helps anyone facing the same issue.