Using Microsoft Purview eDiscovery for Data Investigation

Using Microsoft Purview eDiscovery for Data Investigation

05/08/2025

This technical and educational article is intended to guide security analysts, IT administrators, and systems engineers in using Microsoft Purview eDiscovery to conduct data investigations effectively and compliantly. The ability to identify, collect, review and preserve information relevant to litigation, internal investigations or regulatory requests is critical. Microsoft Purview eDiscovery offers a set of solutions that simplify this complex process, ensuring data integrity and chain of custody [1].

Introduction

eDiscovery refers to the process of identifying, collecting, processing, reviewing, and producing electronically stored information (ESI) in response to a legal or investigative request. Microsoft Purview eDiscovery is an integrated solution that allows organizations to manage the entire eDiscovery workflow within the Microsoft 365 ecosystem, from initial research to final data review and export [2].

This practical guide will cover the concepts of different eDiscovery solutions, such as creating and managing cases, performing content searches, reviewing data, exporting results, and configuring permissions.

Why is Microsoft Purview eDiscovery crucial?

  • Regulatory and Legal Compliance: Helps comply with legal and regulatory requirements.
  • Accurate Data Identification: Allows you to search and identify relevant information across multiple Microsoft 365 sources.
  • Data Preservation: Facilitates the placement of legal holds on data.
  • Cost and Time Reduction: Automates many aspects of the eDiscovery process.

Prerequisites

  1. Microsoft 365 Licensing: A subscription that includes eDiscovery features (e.g. Microsoft 365 E3 for Standard, E5 for Premium) [3].
  2. Administrative Access: An account with appropriate permissions in the Microsoft Purview compliance portal (e.g. eDiscovery Administrator).

Step by Step: Configuring and Using Microsoft Purview eDiscovery

1. Understanding eDiscovery Solutions

  • Content Search: Basic tool for searching mailboxes, SharePoint sites, OneDrive and Teams. Does not include case management or legal holds [4].
  • eDiscovery (Standard): Adds case management, legal holds, exporting results, and assigning permissions to case members [5].
  • eDiscovery (Premium): The most advanced solution, with data processing, text analysis, duplicate detection, theme analysis and document review [6].

2. Assigning eDiscovery Permissions

  1. In the Microsoft Purview compliance portal (https://compliance.microsoft.com), go to Permissions.
  2. Under Microsoft Purview Roles, click Roles.
  3. Find the eDiscovery Administrator role group and add the users or groups that will need access to the resources.

3. Creating an eDiscovery Case (Standard)

A case is a logical container for all information related to an investigation.

  1. In the compliance portal, select eDiscovery > eDiscovery (Standard).
  2. Click + Create a case.
  3. Give the case a Name and Description and click Save.

4. Creating a Legal Hold

A legal hold preserves content so it can't be deleted or changed.

  1. Dentro do seu caso de eDiscovery, selecione Retenções.
  2. Click + Create retention policy.
  3. Give a Name and Description.
  4. Under Locations, select data sources (mailboxes, sites, OneDrive, Teams) and add specific users/groups.
  5. (Optional) Add Conditions to refine the content to retain.
  6. Review and Create this policy.

5. Conducting Content Research

Use the content search tool to find relevant information.

  1. Within your eDiscovery case, select Searches.
  2. Click + New search.
  3. Give a Name and Description.
  4. Under Locations, select the data sources to search.
  5. Under Conditions, define your search criteria using keywords, dates, senders/recipients, file types, etc. You can use KQL (Keyword Query Language) syntax.
    • KQL example: (ProjectX OR "confidential information") AND (date>=2024-01-01 AND date<=2024-12-31) AND (from:"[email protected]")
  6. Click Save and Run.
  7. After the search is complete, you can view the statistics and search results.

6. Exporting Search Results

After searching, you can export the results for review.

  1. On the Searches page for your case, select the completed search.
  2. Click Actions > Export results.
  3. Choose export options (e.g. include non-searchable items, export to a PST file, etc.).
  4. Click Export.
  5. To download the results, go to eDiscovery (Standard) > Exports and use the eDiscovery Export Tool to download the files.

7. eDiscovery (Premium) - Overview

For complex investigations, eDiscovery Premium offers:

  • Data Processing: Normalization, removal of duplicates, detection of threaded emails.
  • Advanced Analysis: Text analysis, theme detection, document categorization.
  • Document Review: Tools for reviewers to mark, annotate and classify documents.
  • Advanced Export: More granular and customizable export options.

Best Practices and Security Tips

  • Planning: Before beginning any investigation, carefully plan the scope, data sources, and search criteria.
  • Minimum Permissions: Grant only the permissions required for eDiscovery functions.
  • Legal Holds: Apply legal holds as early as possible to ensure data preservation.
  • Documentation: Keep a detailed record of all actions taken during the eDiscovery process to ensure chain of custody.
  • Training: Train your team on the correct use of eDiscovery tools and organization policies.
  • Monitoring: Monitor Purview audit logs for eDiscovery-related activity.

Conclusion

Microsoft Purview eDiscovery is a powerful and essential tool for any organization that needs to manage data investigations effectively and compliantly. By leveraging its capabilities, from basic content search to Premium's advanced analytics, companies can efficiently identify, preserve, review and produce relevant information, reducing legal and operational risks. Implementing a well-defined eDiscovery process, supported by Purview capabilities, is critical to data governance and organizational resilience.

References

[1] Microsoft. (2023). Overview of Microsoft Purview eDiscovery. [2] Microsoft. (2023). eDiscovery Workflow (Standard). [3] Microsoft. (2023). Licensing for eDiscovery in Microsoft 365. [4] Microsoft. (2023). Content Search on Microsoft Purview. [5] Microsoft. (2023). eDiscovery (Standard) on Microsoft Purview. [6] Microsoft. (2023). eDiscovery (Premium) on Microsoft Purview.