I can send emails through Windows Live Mail, but not receive: Error code 0x800CCC79

I can send emails through Windows Live through my Cox account.  But I cannot receive.  I have uninstalled and reinstalled Windows Live Mail.  I have sent myself an email through this email account and through another.

The following error shows up:

The message could not be sent. The setting for your outgoing email [SMTP] server might need to be configured. To find the server settings for '<Unknown>', please contact your email service provider.

Subject 'Here are the family take home activity sheets for June.'
Server Error: 550
Server Response: 550 5.5.0 <> invalid address
Server: 'smtp.cox.net'
Windows Live Mail Error ID: 0x800CCC79
Protocol: SMTP
Port: 25
Secure(SSL): No

And also:

Unable to send or receive messages for the Cox (slewis36) account. Windows Live Mail couldn't log on to the email server using secure password authentication. Contact your email provider and verify that it supports secure password authentication. To change this logon setting, in the folder list, right-click on the account name, and then click Properties on the shortcut menu. In the Properties dialog, click the Servers tab, and then under Incoming Mail Server, select a logon option.

Server Error: 0x800CCC90
Server Response: -ERR An authentication mechanism MUST be entered
Server: 'pop.cox.net'
Windows Live Mail Error ID: 0x800CCC18
Protocol: POP3
Port: 995
Secure(SSL): Yes

Thanks for your help.

Original title: I can send emails through Windows Live Mail, but not receive