Generally the application you're trying to access has to have an API or some method of adding the message in. In this case, I don't think Yahoo messenger does.
Could you maybe go another route, and use the Yahoo Messenger API that is provided by Yahoo, or build a client that interfaces with the service? There may be a library, like libpurple, that you could use.
I Developed application in C# with crystal reports and created setup file in third party (Advance) Installer.When i installed my application on client system application is working but ...