Microsoft 365 Business and Enterprise subscriptions, among others, feature Exchange Online, which provides increasingly advanced features of Exchange Server without using on-premises infrastructure. OST files store offline Outlook data like emails, contacts, etc. Migration from Office 365 allows importing OST files to keep data intact. The present article guides users about steps to import OST emails to Office 365 without losing messages, or any important information during this transition.
Causes for OST File Migration into Office365
Having your Exchange mailbox data on a cloud platform like Office 365 has many advantages. Emails on Office 365 can be accessed from anywhere by anyone with internet access. Office 365 mailboxes can be opened from any device also such as Android phones, iPhones, tablets, and so on. So, many Exchange users like to keep a copy of their Exchange mailboxes on Office 365. Easy ways to do this could include moving your offline Outlook Data File (OST) to Office 365 accounts. And this can be done in many ways. Both Exchange users and Webmail users can import their OST emails to Office 365 for continuity in their emailing tasks.
Migration to Clouds: Cloud-based email management by migration from on-premises Exchange server to Exchange Online (Office 365).
OST Corruption: Importing files into a new Office 365 mailbox to resolve problems attached to unusable or damaged OST files.
Device or profile changes: Migrating OST data when upgrading devices or reinstalling Outlook while creating a new profile.
Data Consolidation: Bringing together all emails, contacts, and calendars to the cloud for easy access from different devices.
Compliance and Backup: Ensure the security of data in Office 365, which can be predominantly significant in maintaining regulatory compliance and disaster recovery.
Improved collaboration: Sharper productivity and teamwork by connected Office 365 tools, like Teams, OneDrive, etc.
License Optimization: Getting properly aligned with Microsoft 365 subscriptions to optimize the licensing and lower the costs of on-premise infrastructure.
Genuine Method to Import OST emails to Office 365
OST files cannot be imported directly into Office 365. Instead, OST files could be converted to PST format before importing them. You might also consider using a third-party application for importing OST files.
Method 1: Convert OST to PST and Import into Office 365
This method involves multiple steps:
OST to PST Conversion: Export an OST File to a PST File Using Microsoft Outlook in Outlook go to File > Open & Export > Import/Export > Export to a file > Outlook Data File (.pst) Select the mail account or specific folders you want to export.
Upload PST to Azure Storage: Uploading the converted PST files to Azure Blob storage using the Azure AzCopy command-line tool or with the "Drive Shipping" method, which includes copying the PST files to a BitLocker-encrypted hard drive and shipping it to a Microsoft data center. Microsoft charges an upload fee for uploading the PSTs to the Azure Blob storage on your behalf.
Import PST to Office 365: Create Office 365 user accounts and assign licenses. Now, map the PST files to the corresponding Office 365 mailboxes, assign permissions, and upload a CSV file to begin importing the converted OST files into Office 365.
Limitations: This method requires the profile of Outlook that is active and accessible, but it may not work in case the email profile is deleted or if the OST files belong to old or deactivated accounts.
Note: The method is valid under the condition that the Outlook profile is active and accessible through Outlook. In case the email account is deleted or has old/disabled email account OST files, the method will not function.
Method 2: Use a Third-Party Tool
Use a third-party OST to Office 365 converter tool to directly import the OST file into Office 365.
Steps:
Add the OST file as the source and Office 365 mailboxes as the destination.
Select the Office 365 mailboxes to map with the OST files.
Apply filters such as date, item type, and folder exclusion.
Start the migration.
While several tools exist, WebbyAcad OST to Office 365 Converter Software.
Read Relevant Blog:- Open OST file into Webmail
Conclusion
Importation of OST files to Office 365 ensures accessibility and continuity of data. Since there is no direct import access, OST to PST conversion and importation into Office 365 is an option. The procedure entails uploading PST files to Azure Storage and importing them to Office 365 mailboxes. Alternatively, some third-party tools offer a direct import option. None of the search results mentions any third-party tool aside from Kernel Import OST to Office 365. Other tools such as WebbyAcad OST to Office 365 Converter Software can make the process seamless for non-technical users. Therefore, the right method is dependent on technical expertise and data volume.
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