postgres 'psql' command is not recognized in windows environment

Open Command Line

psql --version

if on above line psql version is not displayed, then follow below steps

(For Windows 7 OS)

Mycomputer->Properties->Advanced System Settings->EnvironmentVariables->Path->Edit->
(Donot remove any existing Path)

Add this

;C:\Program Files\PostgreSQL\9.5\bin;C:\Program Files\PostgreSQL\9.5\lib

save it then

Reopen Command Prompt and repeat

psql --version

C:\Users\rumi>psql --version

psql (PostgreSQL) 9.5.0

Assuming you installed PostgreSQL on Windows with the PostgreSQL "One-click" installer packaged by EnterpriseDB, psql is not added to the PATH automatically. That's partly because adding it to the path could otherwise cause confusion when people have multiple versions of PostgreSQL installed.

You need to specify the full explicit path to psql, eg:

"%PROGRAMFILES%\Postgresql\9.2\bin\psql.exe"

or add psql to the user PATH environment variable, see eg this guide.