Below will show you how you can enable SMTP authentication for Microsoft Outlook 2010 :

Microsoft Office 2010

1. Launch Microsoft Office 2010

2. Click File > Info > Account Settings

3. Select Email from the list and click "Change" button

4. Click on "More Setting"

5. Select "Outgoing Server" tab

6. Tick 'My outgoing server (SMTP) requires authentication

7. Click OK after finish configuration.

8.Click "Next" button.

9. In the "Account Settings" window click "Close"

10. Close Outlook and the relaunch it again.

11. Check the network connection ensure you can sent/receive correctly.

12. Done.