help please - batch for avi to mp4

[schriss]

hy all,

i need your help, please.
im trying to convert lots offiles from avi to mp4 with batch. doesn't work that well avidemux starts but poos a message : "can't open file"
heres the code i tried:

set avidemux="C:\Program Files (x86)\Avidemux 2.6\avidemux.exe"
set videocodec=XVID
set audiocodec=MP4
for %%f in (*.avi) do %avidemux% --video-codec %videocodec% --audio-codec %audiocodec% --force-alt-h264 --load "%%f" --save "%%f.mp4"

would be glad if someone can help
thanks,
sc