i have Microsoft Office 2011 for Mac for a few months now and every time i want to use Outlook, it asks to log in.

My email is registered and i have a good password, but when i try to log in it says my password/email isn't registered.. i often tried also to use the product code, but that doesn't work anymore and the weird thing is is that i can normal use word, excel and powerpoint, but not outlook.. please help