I've made several configurations inside a project for different environments, one is debug and another is release
Web.config:
<configuration>
  <connectionStrings>
    <add name="InvitationEntity" connectionString="metadata=res://*/Models.InvitationSystem.csdl|res://*/Models.InvitationSystem.ssdl|res://*/Models.InvitationSystem.msl;provider=System.Data.SqlClient;provider connection string="data source=192.168.7.131;initial catalog=Invitation_Debug;persist security info=True;user id=invitation;password=debugMe;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
  </connectionStrings>
  <appSettings>
    <add key="FilePath" value="D:\temp"/>
    <add key="debugMode" value="Y"/>
  </appSettings>
</configuration>
Web.debug.config:
   <?xml version="1.0" encoding="utf-8"?>
    <!-- For more information on using web.config transformation visit http://go.microsoft.com/fwlink/?LinkId=125889 -->
    <configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
      <!--
        In the example below, the "SetAttributes" transform will change the value of 
        "connectionString" to use "ReleaseSQLServer" only when the "Match" locator 
        finds an attribute "name" that has a value of "MyDB".
        <connectionStrings>
          <add name="MyDB" 
            connectionString="Data Source=ReleaseSQLServer;Initial Catalog=MyReleaseDB;Integrated Security=True" 
            xdt:Transform="SetAttributes" xdt:Locator="Match(name)"/>
        </connectionStrings>
      -->
      <system.web>
        <!--
          In the example below, the "Replace" transform will replace the entire 
          <customErrors> section of your web.config file.
          Note that because there is only one customErrors section under the 
          <system.web> node, there is no need to use the "xdt:Locator" attribute.
          <customErrors defaultRedirect="GenericError.htm"
            mode="RemoteOnly" xdt:Transform="Replace">
            <error statusCode="500" redirect="InternalError.htm"/>
          </customErrors>
        -->
      </system.web>
  <connectionStrings xdt:Transform="Replace">
        <add name="InvitationEntity" connectionString="metadata=res://*/Models.InvitationSystem.csdl|res://*/Models.InvitationSystem.ssdl|res://*/Models.InvitationSystem.msl;provider=System.Data.SqlClient;provider connection string="data source=192.168.7.131;initial catalog=Invitation_Debug;persist security info=True;user id=invitation;password=debugMe;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
      </connectionStrings>
    </configuration>
Web.live.config:
   <?xml version="1.0" encoding="utf-8"?>
    <!-- For more information on using web.config transformation visit http://go.microsoft.com/fwlink/?LinkId=125889 -->
    <configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
      <!--
        In the example below, the "SetAttributes" transform will change the value of 
        "connectionString" to use "ReleaseSQLServer" only when the "Match" locator 
        finds an attribute "name" that has a value of "MyDB".
        <connectionStrings>
          <add name="MyDB" 
            connectionString="Data Source=ReleaseSQLServer;Initial Catalog=MyReleaseDB;Integrated Security=True" 
            xdt:Transform="SetAttributes" xdt:Locator="Match(name)"/>
        </connectionStrings>
      -->
      <system.web>
        <!--
          In the example below, the "Replace" transform will replace the entire 
          <customErrors> section of your web.config file.
          Note that because there is only one customErrors section under the 
          <system.web> node, there is no need to use the "xdt:Locator" attribute.
          <customErrors defaultRedirect="GenericError.htm"
            mode="RemoteOnly" xdt:Transform="Replace">
            <error statusCode="500" redirect="InternalError.htm"/>
          </customErrors>
        -->
      </system.web>
  <connectionStrings xdt:Transform="Replace">
        <add name="InvitationEntity" connectionString="metadata=res://*/Models.InvitationSystem.csdl|res://*/Models.InvitationSystem.ssdl|res://*/Models.InvitationSystem.msl;provider=System.Data.SqlClient;provider connection string="data source=192.168.7.133;initial catalog=Invitation_Debug;persist security info=True;user id=invitation;password=Invi#2014;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
      </connectionStrings>
    </configuration>
Here's the problem:
Whenever I use debug or release config, the connection string is still the one in web.config instead of that in web.release.config
Is there anything that I did wrong?
 
     
     
    
 
    