One can obtain a list of all installed programs in Windows OS using WMI (Windows Management Instrumentation) command-line interface (WMIC).

To do so, follow the give steps

1. Go to the command prompt.
2. Execute command ‘wmic’ (without quotes)
3. Now you are in wmic interface i.e wmic:root\cli>
4. Now run a command - product get name

This command returns a list of all installed programs.