Immobiliser problem 2003 Renault Clio?

Hi I have a 2003 Renault Clio 1.2 16v and it will not start. When the key is put in the ignition and is turned there is nothing...no sound...nothing. I was told by my local garage this was a starter motor problem so i had a new 1...still not working. They are now telling me it's a fault in my alarm system. If this is the case can i reset the immobiliser my self?? how??