I currently have the same problem with Yahoo.com I cannot log in to my yahoo.com account because they have the comcast.com as my alternative account and that has been closed for a few weeks. I took the chance and opened another yahoo account and have let my friends know my new alternative...
Within the past few days, I tried to login to my Yahoo account. I am sure of the password but their system does not accept it. Recently, I closed my Comcast account due to a better price with Century Link. The only problem is that I didn't change my alternate email from Comcast to another...