May of  Web Hosting customers say that they are unable to send e-mail. They can receive email via outlook but can not send email through Outlook.  Which means that there is some thing wrong with Outlook setting. To fix this issue Please follow these steps.

1- Open Outlook, Navigate to toots-> Account Settings and double click  the account that is not working properly.
2- A New window will open. There details should be like this

3- Now Click More Setting.. and then click Outgoing Server. and check My outgoing server (SMTP) requires authentication and also check Use same as my incoming mail server 

4--Now clieck advanced and set as:: Incoming Server (POP 3): 110, and Outgoing server (SMTP) : 26

5- Now click Ok, then Next > and Finish and click send/receive button and you are ready to go.