Server error: '554 5.7.1 [R8] Authentication Failed, must login

I'm having same problem. This is error message:

Your message did not reach some or all of the intended recipients.

      Subject:    test

      Sent:7/14/2014 11:18 PM

The following recipient(s) cannot be reached:

      '*** Email address is removed for privacy ***' on 7/14/2014 11:18 PM

            Server error: '554 5.7.1 [R8] Authentication Failed, must login.'

The Customer Support

I am unable to send & receive email with my outlook account *** Email address is removed for privacy ***, it shows message on internet explorer as: Sorry, there seems to be a problem with Outlook.com right now.

We are unable to sync message through windows live mail also. Following Error is shown.

Server Error: 0x80048849

Server: 'https://mail.services.live.com/DeltaSync_v2.0.0/Sync.aspx'

Windows Live Mail Error ID: 0x80048820 

Please help.

Regards,

(removed for privacy)

E-Mail: *** Email address is removed for privacy *** / *** Email address is removed for privacy ***U