If you are having trouble sending email, it is probably due to the auth scheme needed to allow you access to send mail using the server resources. What does this mean?

In an effort to prevent unauthorized users from using the server to spam, there are certain measures taken.
These are, your user needs to check their email before trying to send an email. This is so the server may retrieve your ip that your user is logged in from thus given that ip permission to relay email using the server. To ensure the server authorizes your email you may need to adjust your email settings like so:

You'll need to adjust your email settings using these instructions below.
> In outlook, go to
> Tools --> Accounts -->
> Select Mail
> Select the email account
> Select Properties
> Select the server tab
>
> Down the bottom of the page is a checkbox option that says
>
> My Server Requires Authentication
> select it,
> click ok and you're done