I've noticed that a lot of people have had trouble setting up their basic Yahoo! accounts on the Droid Eris (or any 1.5 Android OS). Despite the hype, you do not need to have Yahoo! plus to set it up. I just figured out how to do it. Basically you need to set up an AIM or Gmail account first (this is just to get the necessary menu's exposed). After you've done this, go to account lists and choose the email account you just made, then go to it's settings. Click on account settings (where it says "User name, password, and server"). The first thing you do is change the account email to your Yahoo! email from whatever it was, hit next and again enter the Yahoo! account info such as the user name and password. Under 'imap' enter "imap.mail.yahoo.com" with server port 143 and 'security type' "none". Hit next again and enter your account info once more, then under 'SMTP' enter "smtp.mobile.mail.yahoo.com" with sever port 587 and 'security type' "none". Hit next one last time and it should verify your account info, after this edit the account name to your liking and you should be fine. Once you get into the email just refresh everything so it updates, hope this helps.