MyCase automatically saves a copy of your new message every few seconds and store it under the "Drafts" section of the Messages tab. You can see that a message has been saved as a draft if you see the "Saved" message at the bottom of the new message window. Note: This feature is only available on new messages at this time.
If you have somehow been disconnected from MyCase while creating a new message, you can recover and continue to work on this message under the Messages tab. Navigate to "Drafts" and you will see your unsent message, along with the last time it was saved.
If you would like to remove a saved draft, you can do so by clicking on the red "X" to the right of the message, or by opening the saved message and clicking "Discard Draft".