Windows stores all the wifi passwords for that machines connections in plain text. You can use the Command Line to view any of these passwords in plain text. This can be useful for recovering wifi passwords. Two commands are all it takes to dump the wifi password for your requested network.

Cain and Abel is a password recovery tool for Microsoft Windows. It can recover many kinds of passwords using methods such as network packet sniffing, cracking various password hashes by using methods such as dictionary attacks, brute force and cryptanalysis attacks. Cain and Abel is no longer supported for Windows versions and so to use it with the latest operating systems you will need to add two dll files to your system.