Where is SharePoint web.config?
Ever performed a desktop search to find the web.config file, only to find that there are multiple web.config files on the same server. A number of web.config files are required to configure an IIS web server and SharePoint?
There will be a separate web.config file for each virtual server in IIS which hosts SharePoint site collections. There is also a web.config file for each of the system directories on a SharePoint site, such as the _vti_bin, _layouts, etc. There is also a web.config file which is used to identify trusted web parts.
To find out which directory is used by various SharePoint applications/websites, view the properties of the SharePoint website in IIS and from the “Home Directory” tab, the value in the “Local path” field will take you to the directory where the web.config file is for the specific instance of SharePoint / Application in IIS.
See Where is SharePoint web.config? for more information about the various web.config files which are required to configure SharePoint & ASP.NET web applications, including inforpation about where to find the web.config file for a SharePoint environment.