Flash is required for the use of Audibles, Avatars, and Games within Yahoo! Messenger. The Messenger help pages state that the latest version of Macromedia Flash Player are required to prevent problems with Yahoo! Messenger. You can download Macromedia Flash Player from this link: http://www.adobe.com/shockwave/download/…
Here is the help page I found:
Question: Yahoo! Messenger crashes when I launch it.
Answer: Be sure you have the latest Macromedia Flash Player installed.
Note: Use Internet Explorer to install the player.