Unable to save image as avi...wif ERROR msg popping out

i have already selected my file type as AVI-codec yet my animation could not be saved. a message like tis “ERROR:select an image type in displaybuttons (F10)” pops up

is there anyway i can solve tis problem and save my animation?
p.s. i have no problems saving files in jpeg format.[/b]

oke the process goes like this:
you render a single frame, it is buffered. if you press F3 it saves the buffer. an animation is saved in some other way. you select a directory on the left in displaybuttons. then press “animate”. but hey… it’s all documented…