problems transferring files

I am trying to transfer a movie to the AppleTV for the first time. I have my AppleTv mounted on the finder and inside it a folder called Movies. I am trying to transfer a movie ****.avi and I got the message “Can’t transfer because “Movies” can’t be modified” What should I do? Thank you very much.

Open Terminal and try:

ssh -1 frontrow@appletv.local

Enter frontrow as the password

sudo chmod -R 775 Movies 

If not, you could always SFTP in with cyberduck!
Permission are changable from there (cmd+i)