Lost email after accepting invitation

Solution 1:

Go to your Calendar and click on the Appointment. The contents of the original invitation will be under Start/End time fields (depending on your layout and monitor size, they might be squeezed and difficult to spot at first).

For future you can disable automatic deletion by following:

  1. Go to File tab.
  2. Click Options then Mail.
  3. Under Send messages section you will see a checkbox "Delete meeting requests and notifications from Inbox after responding". Uncheck it.

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