Hey dudes,
I use Outlook 2007 for my e-mailing. I have created 2 accounts connected with two different Gmail Accounts. Everything works fine.
However, I created an new one trying to connect my RoundCube Account with Outlook 2007 with 50% success.
That is, I can receive the messages sent to my RC Account but I CANNOT SEND.
RoundCube is just a webmail client, ask your email provider for help.