You have to check which version of windows you have with you. To check it do the following.
1) On the start button click.
2) On the icon named My Computer right click.
3) Proceed to click on properties
4) On tab named as general , below the system the words “Service Pack X” will be listed (X denotes the service pack you have 1,2).
In case service pack 1 is not installed
Close following applications. Internet Explorer, Outlook Express and Windows Messenger
1) First of all click on start button, Click on option run
2) Type following or copy paste in run line
RunDll32 advpack.dll,LaunchINFSection %windir%\INF\msmsgs.inf,BLC.Remove
3) Finally click on OK
In case service pack 1 is installed
1) First of all click on Start, then goto Control Panel
2) Then proceed to double click on option there add or remove programs
3) There select option of add/remove windows components
4) At that place uncheck option windows messenger
5) Then click on Next
6) Click Finish and restart the computer
For Windows XP SP2
For manual removal do the following
Click on option start, Then click on Run and there enter this command:
RunDll32 advpack.dll,LaunchINFSection %windir%\inf\msmsgs.inf,BLC.Remove
This causes delay in outlook. In order to avoid this delay do following.
Click on Start, Then on Run and type REGEDIT . IN REGEDIT goto
In the right pane right click and then select the new dword value. Name it as “Hide Messenger”. Then double click on this entry and set its value equal to 2.