For the initial troubleshooting step, please reconfigure your account in Windows Live Mail. Do this by removing then re-adding your account. It is possible that there is a problem with the settings and that could be the cause of the error. Also check if there are emails stuck in Outbox , if there are, delete them.
For instructions on how to modify your account in Windows Live Mail, please visit this link.
Note: Before removing an account, check that the messages you want saved are available when you sign in to the web version. If some of your messages are available only in the mail client, export your messages before removing the account.
In addition, if you're still unable to to get back online after re-configuring your account, Follow the steps below to re-establish the connection.
1. Make sure that your default browser is Internet Explorer.
2. Check your computer’s Internet Connection. Verify if Internet Explorer is offline.
a) Open Internet Explorer browser.
b) From the menu bar, click File. (If menu is not shown, press Alt button on your keyboard)
c) Uncheck Work offline by clicking on it.
d) From Windows Live Mail, click Send/Receive button. If you are being asked to go online, click Yes.