error while saving the animation

I’m a new guy. Here’s the annoying problem. I can’t save my work. I get a dialogue, "error while saving the animation set…unable to access file"
any suggestions

a bit more information wouldn’t harm.
what’s the app? is it a trial or a full version? do you have the proper library settings? do you have the proper qt version installed? what’s the platform?

It’s version 3. Full. On a mac running 10.4.5