I have enjoyed being able to check all my e-mail accounts in one place, so despite having the Yahoo! Mail app that was recently put in the Market, I have been using the stock mail app to check my Yahoo! mail. Last night when I checked my Yahoo! Mail through the stock mail app, I was getting weird error messages. Most of the time it would go ahead and put me in my Yahoo! inbox but there would also be a message saying "login failed." I would click OK and then go about my business because e-mails were coming through. I figured it would sort itself out at some point. This morning, it was still doing it and it was annoying, so I re-booted the phone. Same problem. So I decided to delete the account and re-install it (a few weeks ago I had some issues with my Exchange mail account and deleting then re-installing fixed them.) Now, when I try to re-install the account it says "Authentication failed. Please verify your username/password." I have tried it over and over. I know I am using the right username and password - I just used them on my desktop PC to get into the account. And my Yahoo! Mail app still works on the phone. Anyone have any ideas what has happened and/or how I can fix this? I really want to continue to be able to check my Yahoo! mail on my phone without having to use the Yahoo! app.