Thunderbird email passwords

Hi people,

Newbie here so my questions will likely be sorta dumb. I just installed Thunderbird email and am having problems with their password procedure. I registered and then each time i tried to log in, I'd enter my user name and password only to have them denied because they're supposedly invalid. Hence, I cannot get to my email
Any ideas on this would definitely be appreciated.

Thanks.

Ross
camelslot@adelphia.net