text: This is assuming you have the "Automatically Start Yahoo! Messenger" on start up checked in your preferences.  If you don't have that selected, that should fix your problem.  If you DO have it checked off already, hopefully this will help.\n\nI had the opposite problem happen to me---It was launching on startup and I didn't want it to.  Here's what I did:\n\nI went into Messenger Preferences, checked off the "Automatically Start Yahoo! Messenger" on start up, clicked on "Apply," then un-checked it and hit "Apply."  I never had the problem again.