While trying to figure out if email is not being sent in Outlook 2010, following these steps is very helpful to resolve the problem.
Email server is offline
Sometimes Outlook can’t send your messages because your email server is offline–whether an email server at work or online. If that’s the case, keep working! As soon as it comes online, Outlook will send all the messages in your Outbox in a second or two.
You’ll know your server is offline if you see “Disconnected” in the Status bar.
When you’re up and running, it will say “Connected.”