How to run multiple instance of Yahoo! Messenger

To run multiple instance of Yahoo! Messenger, you need a little tweak:

1. Open regedit.
2. Go to key "HKEY_CURRENT_USER\Software\yahoo\pager\Test".
3. Make a new [dword value] and name it "plural".
4. Enter the key and type "1".
5. Exit, restart computer or log off to apply the change you made.

Now, it is possible to login with different Yahoo id at the same time.

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