Exchange - Replay Inbound Messages

This article contains information on replaying messages from Mimecast to Microsoft Exchange, including prerequisites, exporting messages, moving EML files to the Pickup folder, and re-importing emails into the Microsoft Exchange environment.

Introduction

Replaying messages allows you to reconstitute mailbox content from Mimecast into your Microsoft Exchange environment (e.g. due to corruption or data loss). Replaying is a Microsoft Exchange feature that results in correctly formatted email files being submitted for delivery when copied into the correct folder.

Prerequisites

Ensure the messages you are replaying are inbound messages to your internal users. Replaying will reprocess and redeliver the selected messages, so any outbound messages will be redelivered to their intended recipients.

Replaying Messages

Replaying messages requires tasks in Mimecast and on your Exchange Server.

Exporting Messages from Mimecast

You will need to export the Emails from Mimecast, using the following steps:

1. Ensure a Blocked Senders Policy has been configured to prevent open relay, with the From and To variables set to External.
2. Create a Saved Search for the relevant Emails. These should be Inbound emails only.
3. Export the data to a Zipped file containing the individual EML files (default format).

Moving EML Files to the Pickup Folder

You can move the EML files to the Pickup Folder, by using the following steps:

1. Locate the Pickup folder on your Exchange server. This is stored in the C:\Program Files\Microsoft\Exchange Server\TransportRoles directory and may contain other folders (e.g., Shared and Replay).
2. You can find the location of the Pickup folder by using the Exchange Management Shell.

• • Open the Shell.
  • Type the Get-transportserver <servername> | List pickup* command.

Re-importing Messages 

You can re-import messages, by using the following steps:

1. Unzip the file containing the EML files to a folder.
2. Copy the above files to the "C:\ProgramFiles\Microsoft\ExchangeServer\V15|TransportRoles\Pickup" folder. There should be one file per e-mail.
3. The exchange will automatically start importing the Email.
4. You will need to inform users that the missing Emails have been imported.

When messages are placed in the replay folder, Microsoft Exchange automatically batches the messages and sends them to the delivery queue as configured in the Microsoft Exchange environment.
The pickup and replay folders are polled by Microsoft Exchange every 5 seconds for new messages.
For more information, see the following Microsoft articles:

• Pickup directory and Replay directory
• Configure the Pickup directory and the Replay directory

The Email will have a received date of the time of the import, not the time that they were initially received.