I recently installed KB3072333, which is labeled as “Update 1.1 for Microsoft Dynamics CRM 2015”. Afterwards, a specific change to the Outgoing Email Router profile issued a 401 Unauthorized error in the event viewer. I found a fix and am posting it in the hope that it will help someone else!
Specifically, the error prevents emails from actually being sent until this change has been fixed. The error looks like this: “System.Net.WebException: The request failed with HTTP status 401: Unauthorized.”
The simple fix is to go into your Outgoing Email Router Configuration Profile. You can access your Outgoing Email Profile by accessing the “Email Router Configuration Manager” that is found in Start-All Programs on the server where your email router is installed. At the very bottom of the window, check the box that reads “By selecting this check box, you agree to share data from the configured email system with Microsoft Dynamics CRM. Microsoft Dynamics CRM is subject to a separate privacy agreement.” The field you need to change is highlighted in the image below. Once you've checked the box, save your changes by hitting OK at the bottom of the window.
If you open your Outgoing Email Router Configuration Profile back up, you’ll notice that the checkbox will stay checked as it was not before. To complete the fix, simply restart the CRM Email Router Service, and all queued emails should be sent instantly.
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