Here is some information that might help you.
Knowledge of the Outlook version and sometimes the operating system would be beneficial for everyone, especially you.
Fix Outlook.com email sync issues
You can’t send email from Windows Live Mail, a mobile device, or Outlook on your computer
Error occurs when you send or receive an email message in Outlook or Outlook Express
Important This article contains information that shows you how to lower security settings or how to turn off security features on a computer. You can make these changes to work around a specific problem. Before you make these changes, we recommend that you evaluate the risks that are associated with implementing this workaround in your particular environment. If you implement this workaround, take any appropriate additional steps to help protect the computer.
I would be happy to know if I could help.
I know I don't know anything (Socrates)