If you want to run multiple instances of Yahoo messenger, you need to download a third party tool to get you logged in with more than one Yahoo messenger windows. While general Yahoo messenger windows allow a user to sign in with only one user ID at a time, you can download and use this tool to login to multiple Yahoo! accounts at a time and chat with your friends from all logged in accounts. Now you don’t have to sign out from one account to use another.
Download M Multi Yahoo Messenger
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