When you try use your e-mail account to send an e-mail message from Microsoft Outlook, you may get the error below 0x800ccc78 (“0x800ccc78 error: The message could not be sent because the server rejected the sender’s e-mail address”)It is very common but very painful Microsoft outlook problem like Microsoft outlook won’t open… This error may occur if you have not configured Outlook to send user name and password to log on to your MSN e-mail server.
To resolve this problem, following steps are –
Step1: First start Microsoft outlook and click on “Accounts” from “Tools” menu.
Step2: Now click on the “Mail” tab and click your e-mail account, and then click on “Properties” button.
Step3: Now click on “Servers” tab and check to select “My server requires authentication” box.
Step4: Now click on “setting” and click on “Log on using” under Logon Information.
Step5: Now again enter your email and password in given boxes.
Step6: Now check on “Log on using Secure Password Authentication” check box.
Step7: Now click on “OK” to save and click on “OK” to apply setting.
Step8: Now click on “Close” button. Now check that your Outlook Email is working fine without any error. I hope your Outlook will be fixed.