Well, you're not giving much to go on, but did make sure your Caps Lock is off?
Did you make sure your login name is yours? It may have a different login saved if multiple people use CoH on the same computer.
...and just to top this off with some good advice, make sure you don't give your login or password to anyone!
Make sure it is your City of Heroes' account and password not your NCSoft master account and password?
total kick to the gut
This is like having Ra's Al Ghul show up at your birthday party.
any help with this issays i have put in the wrong user name or password after the new download any help