There are many reasons why we want to know the WiFi password previously connected with laptop. Maybe a friend ask for a WiFi password in a cafe ever visited, or maybe because we want to connect a new device to the WiFi.
1. run Command Prompt as Administrator
2. in the Command, Type :
netsh wlan show profiles
next, in the Command, Type :
netsh wlan show profile name = "Profile-Name" key = clear. Profile-Name is the name of the WiFi network we wish to know the password of and without quotes
4. for example, as detail result for WiFi with the name "The_Marble_2EX", the password is '27251981', which can be seen in the Security settings -> Key Content