Error 777

I just downloaded nextgen gallery and I’m trying to set it up to see if it will work for me but when I try to create a new gallery I always get this Error: Directory wp-content/gallery/ didn’t have the permissions 777!

I’ve logged on to my ftp server and changed the permissions number of times, even tried to change the destination name to something else where I knew the permissions were ok but it keeps showing this error…

I also get line errors if I upload folders via ftp to the gallery folder…

any ideas?