aspnet_regiis problem

 Hi all,
         During installation of my web application, i've to decrypt some values from web.config  and perform some changes on my web app with the value. On finishing i've to encrypt it back.I've to put the encrypted( encrypted from my machine) config file on a
different machine, that will generate MSIs and these MSIs have to be
installed on any machine.

         And the web.config looks something like this,
:

        <configuration xmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0">
        <configSections>
          <section name="EncSection" type="System.Configuration.SingleTagSectionHandler" />
        </configSections>
       <connectionStrings>  ...