Answers:
sign in your ym > files> preferences> General>uncheck the box "automatically start ym" > ok
start -> run -> type msconfig -> startup tab -> uncheck ym
Sign in, click the 'Messenger' tab, scroll down to preferences. Click the 'General' tab on the vanished, you should later see the checkbox to start or not start YM on boot up.
goto 'run' type "msconfig" ENTER. goto 'startup' deselect "ym"
Click start > Run... > type msconfig > click on startup tab > find the ym box and uncheck it...thats adjectives..