To improve security, this morning we changed our email configuration to require authentication before sending email.  Previously, if you logged in to check for new mail you would not have to authenticate again to send mail.  This is a security hole in place to work around MS-Outlook.  If your email client (Outlook, Thunderbird, etc.) fails to log in when sending, the only way to make this work is to allow anyone using the same IP address to send without authentication.

Microsoft Outlook assumes you do not need to log in first to send email.  You need to go into the email account settings and tell it to do this.  There are many versions of Outlook with different looking screens and buttons.  To avoid confusion, we will explain what to set in general terms.  In most versions, click on "File" -> "Account Settings" OR "Tools" -> "Accounts".  Next select the account.

We are ONLY concerned with outbound server settings.  Check the box, My server requires authentication.  This is the basis of the problem.

DO NOT check the box, "Require logon use Secure Password Authentication".  If you do, Outlook will crash.

Outgoing server name:  use the name of the server.  To find it you can go to - read the server name after the redirection from the address bar at the top of the browser.

Select "Log on using" - Fill in your email address and password.  Check the box to remember it.

Select if possible  TLS  and port 587.  If you find that doesn't work (or there is no TLS option) select SSL and port 465.

Please note that the server will block logins from an IP address with 10 or more failed logins over the last hour.  This block lasts 1 hour.  Unfortunately, this means that if you have been experimenting you may be blocked.  If you are sure you have it right, wait an hour and try again.

Please be aware that Outlook sometimes fails to keep what you set.  Even after saving settings it sometimes reverts to bizarre values or nothing at all.

Note that our servers are 100% standards compliant.  Email clients written to the standards will work witout any trouble if default values are left in place.  This problem is confined exclusively to Outlook.

Tuesday, August 9, 2016

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