Error Mesagge

Hi,
Whenever I log in I will get the message that I should check my username and my password. Because user name and password are always right and I am not banned, it may be that it is a technical problem? I have changed on 5 April 2010 (yesterday) my e-mail to: daniel260895@hotmail.de. What should I do? If I was banned but would come a message or?
I have specially created a new account so I can post here, because i can't login. Please help me.

Greeting

Daniel260895