Internet Information Services (IIS) is the default web server on Windows installations. The configuration of websites on IIS is stored in a file called web.config and can store passwords for databases or configured authentication mechanisms. Depending on the installed version of IIS, we can find web.config in one of the following locations:

find database connection strings on the file:

type C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\web.config | findstr connectionString