Recently, we guided you about how to add your Facebook Stream, how to hide
the updates from a specific friend or group and how to appear offline for a
specific friend in Windows Live Messenger.

Today, we are going to guide you about how to setup a sound alert for a
specific friend in Windows Live Messenger so that you can hear a different sound
alert whenever your friend signs in or interact with you in messenger. Following
are the steps:
More: How to setup a sound alert for a specific friend in Windows Live Messenger | MicrosoftFeed