Server Error 551 Windows Live Mail

The server error 551 Windows live mail might occur if the SMTP authentication is not enabled. To enable SMTP authentication in your Windows Live Mail email client, proceed with the step-by-step guidelines provided here.

  • Step 1:Open the main window of the Windows Live Mail email client.
  • Step 2:Right-click your email account and click the Properties option.
  • Step 3:Navigate to the Servers tab, select the checkbox beside the ‘My server requires authentication’ option, and click the Settings option.
  • Step 4:The ‘Use same settings as my incoming mail server’ checkbox should be selected.
  • Step 5:Deselect the ‘Log on using Secure Password Authentication’ option.
  • Step 6:Finally, click the OK option.
  • Step 7:This will enable SMTP authentication.
  • Step 8:Another reason for the server error 551 in the Windows Live Mail email client is ‘Sender address is not valid for your login.’
  • Step 9:Some of the possible causes for this server error 551 Windows live mail problem are incorrect server settings, incorrectly configured system files, and virus/adware/spyware attack.

If the Windows Live Mail error ID 0X800CCC6B - Server error 551 occurs in the Microsoft Outlook email client, perform the following steps.

  • Step 1:On the main interface of the Microsoft Outlook email client, click the Work Offline option.
  • Step 2:Click the Outbox folder on the left panel and clear all the email messages present in it.
  • Step 3:Compose a new email message, send it, and check if the problem has been resolved. If not, do the following steps.
  • Step 4:Go to the General tab in the Outlook email client, deselect the Site Default Values option, and select the checkbox next to the Enable Protocol option.
  • Step 5:Click the Authentication icon and select the ‘Response to the NWT Challenge’ or ‘NT Challenge Response using SSL’ option.

If needed, click the Call button to get assistance from our technical support member in resolving the server error 551 Windows live mail problem.