My Nero dvd burner stopped allowing me to add .avi files about 3 months ago. It always gave me an error saying : "Cannot add .avi file" when I would try and create a DVD.
After looking around and not finding ANY solution I just worked it out myself: Here is what I did to get to to work.
The problem: I finally discovered that due to a "rogue" Codec that I loaded (one of those all-in-once codec packages) Nero no longer recognized the .avi format.
The solution: (sorry this requires a Windows Disk -XP, Vista, or win2k)
I booted with the Windows disk in the CD Rom... It loaded and asked what I wanted to do. I proceeded to the "Install Windows" screen. At this point it will determine that you already have windows loaded and give you the option to "Repair" (this is not the "R" option for repair from the command prompt (proceed as though you are re-installing all of Windows)
After a short "re-install" or "repair" of Windows, I rebooted and was finally able to use Nero agiai to burn my .avi files!!!!!!!