What is wrong with yahoo messenger and yahoo web messenger?

yahoo gets crazy sometimes

Make sure those are typed correctly with proper letter Case,no commas,periods or space bar in between the characters Make sure your internet connection is ok and fast,stable and consistent enough to connect you to Yahoo! Server Make sure your windows or other ant-virus firewall is not blocking your communication to Yahoo! Messenger Try all the 'Connection Preferences' ( under 'Messenger' menu on the unsigned Messenger) The server may be busy or heavily loaded with internet 'traffic jam' and so you have to wait for a bit and try again and again If it still can't let you sign in then there may be some technical problem related with communication server,Yahoo! is trying fixing this ,so wait for a while until it get bto normal. *BUT if your Yahoo! ID been canceled for serious 'Violation issue' of 'Community Guideline' or 'Terms of Service' or been hacked for lack of security of your system and consciousness about using it then you can't sign in with it even ID and password are correct,then you have to investigate thru proper links