Combining avi files

I dled a movie and tryed to combine all 3 parts using "avi joiner" but when i try to play the movie after its combined the 3 segments it gives an error msg about the audio..so i tryed using gspot and got an error message saying "Corrupt avi header" does anyone know how i can get this to work?

 

try virtualdub. append avi file. there is a short guide

 

or try easy video joiner
http://www.DoEasier.org/
It will do avi,mpeg, rm, wmv/asf no probs