Many stores, coffee shops, hotels, service stations, pubs etc offer free Wi-Fi.
Sometimes your acquaintance punches in a Wi-Fi password in his/her house for your temporary browsing.
The same method also works on Windows 7, 8 and 8.1. hey confirm that you dont edit the file or you might start having problems with your Wi-Fi connectivity.
So, its better to use this manual method to get the passwords than to install that adware crap.
source: www.techworm.net