Here I am describing how you can install and update Yii in WAMP sever.
Follow the following step by step procedures to find your destination-
Step 1: Assigning PHP engine location path in system variable
Now enter your PHP engine location on end of the "variable value" field
i.e. for me I entered "C:\wamp\bin\php\php5.3.10". Just enter location without double quotes
Click ok and finally exit from this.
Step 2: Create project folder under "www"
Just create a blank folder in "www" that should be your project name. i.e "bid" You can also make this using command window. For this-
Step 3: Download Yii framework and put into www directory and install the framework for bid project
C:\wamp\www\yii\framework>yiic webapp C:\wamp\www\bid
Create a Web application under ‘C:\wamp\www\bid’? [Yes|No] y
Your application has been created successfully under C:\wamp\www\bid.
Now you are ready to browse your project by accessing the URL : http://localhost/bid/
If you want to use this installation for multiple project then just copy "bid" folder and past and rename with your project name. Its better if you make "bid" folder as your backup project folder then when you need to work with a new project then just you need to copy and past this folder and rename to your new project name.
If you want to install an updated version of Yii framework then please download updated version zipped folder from "http://www.yiiframework.com/" and unzip. After unzip the file just copy the framework folder and then go "yii" folder under "www" directory and just replace previous framework folder with latest one.
Enjoy and explore Yii...........