video gone corrupt

[beep911]

Hi,
I really hope someone can help me, I have a video made up and transferred it to .m4v for appletv2, but after I put it into itunes I went to...right click...get info...options...media kind to podcast...then my itunes hung for a bit...then had to force quit. Now my file is corrupt and will not play at all...is there any way to fix it...a program that can maybe help...please.....
I found a program called "Treasured", says it can fix my movie file, but they want money
Anyone know of another program that can do the same as this Treasured program?
The Treasured progam will even show the video, but wont fix it unless I pay, is there a program that will do the same, I would buy a program to have, but I dont like the idea of paying each time I need to do this
itunes was just changing the media kind to podcast, so I think the video is fine, its just the coding or something.

[Baldrick]

Try some editors like avidemux, mpeg streamclip. If it can open it, then save as a new mp4.

[beep911]

when i try to open it with quicktime it says, 'An invalid public movie atom was found in the movie.'
If I try to open it with VLC it just plays as a green screen.
Will those programs.

Thanks for replying

also, how can I save it as a new mp4 if I can not open it?