When the EnableScriptLocalization property is set to true, the ScriptManager object will retrieve script files for the current culture if they exist. For example, a page might specify a script file that is named CustomScript.js. If the culture is set to fr-CA, the ScriptManager object will try to retrieve a script file that is named CustomScript.fr-CA.js.
To prevent a script file from being rendered two times, the EnableScriptLocalization property must not be modified during an asynchronous postback.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)