I've just installed Thunderbird and while it recognizes the correct settings for my e-mail address (Verizon/AOL), it won't accept my password. I re-typed everything in case of typo, logged into my account on the AOL Mail site perfectly, and have tried changing the password (still didn't work), made sure I have have two-step authentication turned off, and that I am allowing apps "that use less secure sign in". I still constantly get the "configuration could not be verified - is the username or password incorrect?" message. Last month I configured my father's account on his computer and went through the same steps quite smoothly, and he uses the same Verizon/AOL service. I'm not sure what to do at this point so any help would be appreciated. EDIT: This problem has been solved. After playing around a little bit we discovered the anti-virus program was preventing it from authenticating properly. We temporarily disabled the program and later added Thunderbird to the whitelist.