How do I retrieve old emails on Exchange?

Question

We need to retrieve emails that were sent to a customer from November 2022 to March 2023 for legal reasons. Our company uses Microsoft Exchange and messages disappear after 12 months. Is there a way to retrieve them?

Answer 1

Hi Kate Merson,

Welcome to Microsoft Q&A Forum!

Have a good day and I hope you're doing well!

Based on my research, in Exchange Online, emails that are no longer visible in a user’s mailbox may still be recoverable depending on how your organization’s retention and compliance features were configured at the time.

In Microsoft 365, historical emails are typically retrievable only if they are still preserved by compliance mechanisms such as eDiscovery, Litigation Hold, or other retention policies. Even when messages disappear from the mailbox after a defined period, they may still exist in the service’s compliance storage.

A common approach is to use Content search (eDiscovery) in the Microsoft Purview compliance portal to search across Exchange Online mailboxes for messages that match a specific date range, sender, recipient, or keywords. If the emails from November 2022 to March 2023 are still retained under your organization’s policies, they should be discoverable and exportable from there.

You can find more details on how mailbox content is searched in eDiscovery in the following Microsoft documentation:

• Finding content in mailboxes in eDiscovery | Microsoft Learn
• Getting started with the new Purview Content Search

However, it’s also important to note that if those emails were permanently deleted and no retention or legal hold was in place at the time, Exchange Online may no longer have a copy available to retrieve.

I would recommend checking with your Microsoft 365 or compliance administrator to review:

• Whether eDiscovery or retention policies were applied during that period, and
• Whether a Content search in Purview can still locate the required messages.

I hope this helps clarify the available options, at least partially. If I’ve misunderstood anything about your setup, or if you have any updates to share, please feel free to let me know.

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Answer 2

What if the retention period has expired?

Answer 3

To retrieve old emails in Microsoft Exchange, you can utilize the In-Place eDiscovery feature or the Search-Mailbox cmdlet. Here are the steps you can follow:

1. Check Deleted Item Retention: Ensure that the deleted item retention period has not expired. In Exchange, this is typically set to 14 days by default, but it can be configured for longer periods.
2. Use In-Place eDiscovery: This allows you to search for emails across multiple mailboxes. You can access this feature through the Exchange admin center (EAC). It enables you to search for emails sent to a specific customer during the specified date range (November 2022 to March 2023).
3. Search-Mailbox Cmdlet: If you have administrative access, you can use the Search-Mailbox cmdlet in PowerShell to search for emails in a specific mailbox. For example, you can specify the date range and other search criteria to find the relevant emails.
4. Recoverable Items Folder: If the emails were deleted, they might still be in the Recoverable Items folder, from which you can recover them if the retention period has not expired.
5. Export to PST: If you find the emails using In-Place eDiscovery, you can export them to a PST file for legal purposes.

Make sure you have the necessary permissions to perform these actions, and consult your IT department if you need assistance with the process.