Seting up on another workstation and needs password

i am trying to set up Thunderbird on a second computer on my retail store. I have loaded it and said I want to use my own email and it brings me to a pop up box to enter my name, email and password. I do that and it tells me that it found my email address but when I hit DONE it tells me the user name or password is incorrect. Is there something else i need to set up. i only have one user name and password which is the same one i used to log into this information request. What am i doing wrong ??