Microsoft Outlook has been one of the most widely used desktop email clients for decades. It stores emails, contacts, calendars, and other data in a file format known as PST (Personal Storage Table). While PST files allow offline access and portability of email data, they also come with limitations, such as the risk of corruption and limited accessibility across devices.

On the other hand, Office 365 (Microsoft 365) is a cloud-based platform offering robust email management, advanced security, and anywhere accessibility. For users and organizations transitioning to the cloud, moving PST files into Office 365 ensures that all email data is securely available anytime, anywhere.

This blog explains what PST files and Office 365 are, why importing PST files is important, the manual method to add PST to Office 365, its limitations, and a better alternative for smooth migration.

Overview of PST File and Office 365

A PST file is an Outlook data file that stores a user’s email messages, contacts, calendars, tasks, and more. It is primarily used when Outlook is configured with POP accounts or when users need to back up and export mailbox data.

Office 365 is Microsoft’s cloud-based productivity suite that includes Outlook (Exchange Online), Teams, OneDrive, and SharePoint. It offers advanced collaboration tools, enhanced data security, and accessibility from any device, making it the preferred email platform for modern businesses.

Reasons to Add PST Files to Office 365

There are several reasons why users prefer importing their PST data into Office 365 -

• Centralized Mailbox – Keep all past and present email data in one account for easy management.
• Anywhere Access – Check your emails from any device without relying on locally stored PST files.
• Security & Compliance – Office 365 ensures enterprise-level security, encryption, and data compliance.
• Data Backup & Recovery – Cloud storage provides better protection against corruption and accidental loss.
• Collaboration – Office 365 integrates seamlessly with Teams, OneDrive, and SharePoint for improved productivity.

Manual Method to Add PST Files to Office 365

Microsoft provides multiple built-in methods for migrating PST files into Office 365. These include the Network Upload Method and the Drive Shipping Method.

1. Network Upload Method

In this process, the PST file is uploaded over the network to Microsoft’s cloud. Steps include -

• Sign in to the Microsoft 365 Compliance Center with admin credentials.
• Open the Import Service and choose the Upload PST Files option.
• Download and install the Azure AzCopy tool to upload PST files to Microsoft’s temporary cloud storage.
• Create a CSV mapping file to specify which PST file goes to which mailbox.
• Start the import job from the Compliance Center and monitor progress.

2. Drive Shipping Method

In this method, users ship their encrypted PST files on a physical hard drive to Microsoft, who then uploads them into Office 365. This is suitable for organizations with limited bandwidth or very large PST files.

Limitations of the Manual Method

While the above methods are official, they come with significant drawbacks -

• Complex Process – Requires technical knowledge and multiple tools (AzCopy, CSV mapping).
• Time-Consuming – Uploading large PST files takes hours or even days.
• Risk of Errors – Any mistakes in CSV mapping can lead to failed imports.
• Admin-Level Only – Non-technical users may find it extremely difficult to perform.
• No Selective Import – Imports entire PST files without allowing filters for specific folders or emails.

Alternate Way on How to Add Outlook Data File (PST) to Office 365

To avoid the complexities of manual migration, many users prefer BitVare PST Converter for Mac & Windows OS make it simple to import PST files into Office 365 with just a few clicks.

Key Features -

• Direct Import to Office 365 – Upload PST files directly into your Office 365 account without extra steps.
• Batch Import – Migrate multiple PST files at once, saving time and effort.
• Selective Migration – Apply filters by date range, folder, or subject to move only required emails.
• Data Integrity Protection – Retains the original folder hierarchy, email formatting, metadata, and attachments.
• Cross-Platform Availability – Works on both Windows and Mac systems.
• User-Friendly Interface – Designed for both technical and non-technical users.

Conclusion

Moving PST files to Office 365 ensures secure, centralized, and easily accessible email data. While Microsoft’s manual methods (Network Upload and Drive Shipping) are available, they are complex, time-consuming, and suitable only for technically skilled users or large enterprises with IT support.

For a simpler and more reliable process, using a professional PST to Office 365 Tool is the best choice. It enables seamless PST to Office 365 transfer with robust security and smart filter options, ensuring a hassle-free move for both personal and business users.