My Outlook 2007 Won't Send My Emails
Microsoft Outlook is used by both corporate and home users to manage email, calendars and RSS feeds. Outlook handles all popular mail protocols including Microsoft Exchange, POP3, IMAP and SMTP. Understanding where to begin troubleshooting and then eliminating possible causes is the easiest way to diagnose and ultimately fix a send-mail issue in Outlook. When Outlook is unable to send mail, the issue is likely to be a network connectivity issue.
Check your network and Internet connection. If you are unable to send or receive, this may indicate a network connectivity issue. A loose cable or poor wireless signal may be to blame. Check the network cable plugged into a LAN port or your wireless network connection indicator. Reset or replace the cable if it is loose or try moving to an area with a better signal if you have less than two bars on your wireless network connectivity indicator.
Check that Outlook has not enabled Offline Mode. Outlook has a mode called Offline Mode which will allow users to interact with the cached version of their mailbox if they are not connected to a network. Outlook will enable Offline Mode when it detects no connection to the network or if it detects a slow connection to the network, but users can also manually enable Offline Mode as well.
Check send-mail settings in your Account profile. If you have recently changed your password or your ISP notifies you that there have been changes to your mail account, these might affect Outlook's ability to send mail. Go to your account settings by going to "Tools" in the menu bar and then selecting "Account Settings." Choose the account that you are trying to send from and verify that your username, server name and password are all correct. Test your settings by clicking the "Test Settings" button.
Investigate possible blocked ports. If you have eliminated all other possible causes for sending-mail issues and can receive mail, there is a possibility that sending mail is blocked at the network level. This can happen on private networks, such as corporate networks, which disallow sending mail from anything but their own mail servers due to security concerns. If you suspect that the port may be blocked, contact the network administrator of the network you are working on. In a corporate environment, a network administrator may give you a workaround, if one exists. Some Internet Service Providers may also block SMTP senders that are not their own. In a home environment, the ISP may specify a specific approved mail server to use.