Import PST to Office 365: IT Admin Guide for Bulk Migration

What Does It Mean to Migrate PST to Office 365?

A PST file is an Outlook Data File that stores emails, contacts, calendars, tasks, notes, and attachments. Importing PST to Office 365 means transferring this data into Microsoft 365 mailboxes so users can access it from Outlook, Outlook Web App, and mobile devices.

Reasons to Import PST File to Office 365

• Office 365 allows users to access emails from anywhere using Outlook Web, desktop Outlook, or mobile devices.
• Microsoft 365 provides advanced security, spam protection, and backup infrastructure.
• Organizations can manage multiple user mailboxes through a single admin panel.
• Large PST files consume local disk space. Moving data to Office 365 reduces reliance on local storage.
• Also, many companies migrate from old Outlook environments to Microsoft 365 for better productivity.
• Similarly, users who Import PST to AOL Mail may later move to Office 365 for enhanced security, compliance controls, and enterprise collaboration features.

Import PST to Office 365 Using Microsoft’s Azure Upload Method

Microsoft provides a Network Upload method that allows administrators to upload PST files to Microsoft Azure Storage and import them into Microsoft 365 mailboxes.

Step 01: Assign Required Permissions

• Begin by signing in to the Exchange Admin Center using an administrator account.
• Navigate to: Permissions → Admin Roles → Organization Management
• Open the Organization Management role group and assign the Mailbox Import Export role. 
• Save the changes and allow some time for the permissions to propagate throughout the Microsoft 365 environment.

Step 02: Create a PST Import Process

• Next, sign in to the Microsoft Purview Compliance Portal.
• Navigate to: Data Lifecycle Management → Import.
• Click New Import Job, provide a unique job name, and select Upload Your Data (PST Files) as the import method.

Step 03: Upload PST Files to Azure Storage

• After creating the import job, Microsoft generates a Secure Access Signature (SAS) URL.
• Now: Download and install Azure AzCopy.
• Copy the SAS URL provided by Microsoft.
• Connect AzCopy to Azure Storage.
• Upload the PST files using the AzCopy command-line utility.
• The upload duration depends on the PST file size and internet speed.

Step 04: Create a CSV Mapping File

• Prepare a CSV mapping file that links each PST file to its destination Microsoft 365 mailbox.
• The CSV file should contain: PST file name, target mailbox address, and additional mapping details required by Microsoft
• Carefully verify all entries before saving the file, as incorrect mappings can cause import failures.

Step 05: Validate and Start the Import PST File into Office 365

• Return to the Microsoft Purview Compliance Portal and upload the CSV mapping file.
• Microsoft will validate the mapping information and identify any errors. Once validation is complete, select Start Import to begin the migration process.
• Monitor the job status until all PST data has been successfully imported into the target Office 365 mailboxes.

Limitations: Manually Open PST File in Microsoft 365

• Requires multiple administrative configurations before migration begins.
• Demands technical knowledge of Exchange Admin Center, Microsoft Purview, and Azure tools.
• Creating and validating CSV mapping files can be time-consuming.
• A small mapping error can cause migration failures.
• Upload speed depends entirely on the internet bandwidth.
• Troubleshooting failed imports can be complex.
• Not ideal for large-scale or enterprise PST migrations.
• Limited flexibility for selective mailbox migration.
• Managing multiple PST files becomes difficult as migration volume increases.

Professional Tool to Import PST to Office 365

For organizations handling multiple PST files, the manual Azure upload method can become complex and time-consuming. In such cases, a professional solution like the DRS Softech PST Converter Tool offers a faster and more streamlined way to import PST files.

The software is designed to migrate Outlook PST files directly to Microsoft 365 mailboxes while preserving the complete mailbox structure. It supports emails, contacts, calendars, tasks, notes, and attachments without data loss. The tool is particularly useful for IT administrators managing large-scale migrations or multiple user mailboxes.

Apart from Microsoft 365 migration, the software also supports multiple email platforms. Organizations looking to Import PST to Opera Mail can use the same solution to transfer Outlook data while maintaining folder hierarchy, attachments, and mailbox properties throughout the migration process.

Simple Steps to Migrate PST to Office 365

1. Download and install the DRS Softech PST to Office 365 Migration Tool.
2. Choose “Select Files” or “Select Folder” to add your PST files.
3. Preview and select the PST files to open. Click Next.
4. Select Office 365 as the Saving Format and enter your Office 365 Email Address and Password to Sign In.
5. Lastly, apply advanced features and filters as needed. Press Start Export.

Conclusion

In this complete blog post, we explored several methods to import PST to Office 365. The manual method is only used to import a small number of PST files. However, it has several limitations. Therefore, it’s best to use the professional tool. It converts multiple PST files at once with no data loss. You can also download the free version of this tool to evaluate its features. If you have any queries related to this tool, feel free to ask our technical support. They are 24/7 available and resolve your query instantly.

Frequently Asked Questions