yiic webapp D:\wamp\www\test
sh.exe": yiic: command not found
yii webapp D:\wamp\www\test
Error: Unknown command "webapp".
You don't need yiic for installing Yii2 see the getting started guide for all the information you need . You can install really easly with composer
http://www.yiiframework.com/doc-2.0/guide-start-installation.html
Use init command in yii2
C:\xampp\htdocs\advanced>init
Yii Application Initialization Tool v1.0
Which environment do you want the application to be initialized in?
[0] Development
[1] Production
Your choice [0-1, or "q" to quit]