In Windows Live Messenger 2009 (current version installable through Windows Live Essentials),
Microsoft has added support for running multiple instances of Windows Live Messenger,
allowing user to sign in to multi-login and log on to multiple accounts.
The helper external third party programs such as MultiLive or MultiMSN no longer required.
The support for multi-WLM is not enabled by default, but can be easily turned on and enable with registry hack.
1.Run Registry Editor (regedit).
2.Navigate to the following registry key:
For 64-bit (x64) OS, go to following registry branch instead:
3.In the right pane, right click on any blank space, select New on context menu, and then click on DWORD (32-bit) Value.
4.Name the new registry value entry as MultipleInstances.
5.Modify the MultipleInstances and set its value data as 1.
6.Start as many Windows Live Messenger windows as you want from Start Menu.