Calendar E-Mail Extension – How to troubleshoot incoming email issues

With the Calendar E-Mail Extension you can send invites from a SharePoint calendar to attendees’ mailboxes and handle their replies. But this is only one feature provided by the Calendar E-Mail Extension. It is also possible to send an invite to the SharePoint calendar from Outlook.

In this post I will explain how meeting requests are processed from the calendar with email extension. This should help you to troubleshoot your problem if events sent from Outlook or any other email client do not appear in the SharePoint calendar.

A SharePoint standard calendar is also able to receive events sent to the calendar’s email address. The Calendar E-Mail Extension is based on a SharePoint calendar but is also able to send invites from SharePoint to attendees and handles their responses. Because of this feature, the calendar looses the ability to receive events (we use our own email receiver), but we have implemented a workaround to make this possible again. Here is how it works:

When you send a meeting request to a calendar list with the e-mail extension enabled, the calendar receives the email and creates an empty event.
After this it tries to forward the meeting request via email to a second (hidden!) calendar list, which processes the event again and does all the miracles SharePoint does when it creates an event from a meeting request.
Finally the e-mail extension takes all the information and continues processing the original request.
This means, that once the first email has been processed an event should be created (Event Date and End Date are both 01/01/0001, so you won’t see it in the calendar view). If you switch to the “All events” view, you should see it. After the second email has been processed, the previous event should be updated with the values from the meeting request.

If an event does not appear in the SharePoint Calendar, you can check the following:

  • First make sure incoming emails are configured correctly. If this is the case you should see an email (eml file) pop up in the email drop folder of your SharePoint application server (usually C:\inetpub\mailroot\Drop).Drop Folder
  • Keep an eye on the drop folder while the incoming emails are processed.
    You should see an eml file appear when you send the meeting request to SharePoint. This message should be replaced a few minutes later with another eml file. Another few minutes later the second eml should disappear.

    The time depends on the timer job settings of the immediate alert job.
    Drop Folder

  • Check if an event with no title and no start and end date has been created once the first email has disappeared from the drop folder. Go to the “All Events” view to make sure everything is visible.

If you cannot solve this problem, send an email to [email protected] explaining exactly what your problem is.