Why do I keep getting an error message when I try to change my yahoo profile picture?

It's a glitch and no one knows what's going on. I don't even think the staff know what to do. If they know about it, chances are they are working to fix it, but if you're still unsure, hover your mouse over the ABOUT tab at the top and go to the Suggestion Board. Post the situation there as a BUG; see if they respond to it.