Nero Mpeg 4 codec prob



Hello people,
I am trying to burn a file with Nero. I have the most recent version of nero burning rom and nerovision express.
When i try to add the file i wish to burn, which is an Xvid Mpeg 4, it tells me that Nero cannot burn this file (or something along those lines) and i need to buy something or get the web version.
I have used Gspot on the file and i have all the proper codecs installed on my comp.
In nero however, only the audio file is showing up to be burnt.

Can anyone help me and i am sorry if i havent explained this very well!!
Thanks in advance!