When i sign in yahoo messenger its display error message?

first try logging into yahoo manually to make sure they haven't scrapped your account. It doesn't take much of an infraction for them to do that. If that doesn't work uninstall YIM and reboot, reinstall and use a program like CCleaner to to remove it from the startup sequence, reboot, let everything go online and then try to boot it when nothing is interfering with the login sequence.