The installation of SharePoint comes with two versions of each of its script files such as sp.js and sp.debug.js – the debug versions of the files contain the unminified code.
These files can be found at
C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\TEMPLATE\LAYOUTS
SharePoint has an option, which loads the debug versions of its scripts rather than the minified version.
In order to set this property, go to
Open the folder with number corresponding to the port at which SharePoint is running.
Locate web.config and open it to find the following line
<compilation batch="false" debug="false">
Replace it with
<compilation batch="false" debug="true">
After this step I use
in Command Prompt to restart SharePoint and apply the debug setting.
You can add
<deployment retail="false" />
to the <system.web> section of the web.config file – Client Object Model Distribution and Deployment.