Microsoft Outlook throws an error while sending an email (

 As you have mentioned the Out Look Express is not allowing you to send E-mails because something is preventing Outlook Express of accessing your Network.

You can resolve this issue by following the steps mentioned below.

1. Click on the Start button in the desktop.
2. Then select “Run”.
3. Type in “cmd” in the text box and then hit enter button in the key board.
4. You will be able to see the command prompt, the one with the black screen.
5. Now, type the command “netsh winsock reset” in the command prompt and click enter button from the keyboard.
6. Now, close the command prompt and restart your computer and try again with Outlook Express.

Steps to be followed if you are using Windows Vista

1. Click on the start button and type “cmd’ in the search box and hit enter from your keyboard.
2. Type in the command “netsh winsock reset” in the command prompt and press enter.
3. Restart the PC and check if the issue is resolved.

The error 0x800CCC12 in Microsoft Outlook can mean a number of things. It could be a Winsock socket error, in which the program is unable to send the Winsock request. To fix this, you would need to uninstall the TCP/IP and reinstall it by going into the control panel and accessing the Network folder. Or, it could be a destroyed or corrupt registry file, usually caused by a virus, or by installing or updating a program without removing other applications related to the program, causing the error. To fix this, you must download a registry tool program that, once installed, will scan and automatically repair registry errors.