How to Import OST to Office 365 - A Complete Guide

Office 365 (Microsoft 365) is a very popular cloud service developed by Microsoft. With the help of this service, you can easily access Microsoft’s top applications like MS Word, Excel, Outlook, Lync, OneNote, PowerPoint, etc. in any device from any location. After its release, many Exchange users started migrating their Exchange mailboxes to Office 365 accounts and the subscription base of the Office 365 is increasing day by day. But migrating Exchange OST to Office 365 is not an easy task.

In this post, we will discuss manual methods to import OST to Office 365 and how to migrate OST to Office 365 using third-party software.

How to migrate OST to Office 365 manually?

There is no direct manual method available to migrate OST to Office 365. To perform this method, first, you need to convert OST to PST format and after that, you can use the Microsoft Network upload method to upload PST to Office 365.

Step 1: Convert OST to PST Format

1. Open MS Outlook and click on File option
2. Select Open & Export option and choose Import & Export option
3. Select Export to a file and click Next button
4. Select outlook data file (PST)
5. Choose the folders you want to export, select the checkbox to include sub-folders, and click on Next.
6. Set a location to export and click on the Finish button.

Note: This export method will work only if the user account is connected to the Exchange Server.

Step 2: Upload PST to Office 365

1. Sign in to your Office 365 account
2. Go to Admin Center of Exchange Server
3. From the Exchange Admin Center window, select Permissions and double click on Organization Management.
4. From the new pop-up, click the “+ sign” and select the Mailbox Import Export.
5. Click on the Add and choose OK
6. Now, select Mailbox Import Export again and choose Save
7. Go to the Admin Center
8. Select the Setup followed by Data Migration
9. Click on the Upload file
10. Select the New Import Job
11. Type the job name and click on the Next. Use lowercase letters, numbers, hyphens, and underscores.
12. Select Upload Your Data option from the Do you want to upload or ship data? Window and then click on Next
13. On the Import data page, click on the Show network upload SAS URL
14. Copy the displayed SAS URL
15. Click on the Download Azure AzCopy to download and install the tool
16. Go to the directory where you installed the AzCopy.exe tool
17. Run the following command

    AzCopy.exe /Source:<Location of PST files> /Dest:<SAS URL> /V:<Log file location> /Y

    After running the command, it displays status messages.

18. Create a CSV file that specifies which user mailboxes the PST files will be imported to. ( Download sample CSV file )
19. Go to Import data page and select I'm done uploading my files and I have access to the mapping file check boxes and click on the Next button
20. On the Select, the mapping file window click on the +Select mapping file option and provide CSV mapping file
21. Click on validate. After click on the validate file name is changed to green after it's successfully validated
22. Click on the Save and Close

Note: This is method is long and complex. If you don’t have a technical background then try OST to Office 365 migration tool . With the help of this software, you can easily convert OST to Office 365 without hassle.

Import OST to Office 365 using Third-party OST Converter

1. Download and install the SysCurve OST to Office 365 tool
2. Click on Add File option, select OST file and click on OK
3. After the loading process, the software will generate a complete preview of your data
4. Now, Click on the Export option and choose either Export All Folders or Export Selected Folders option
5. Select Office 365 as an Export option
6. Set a location for the log file and click on the Next button
7. From the Export to Office 365 window, select either Export to Primary Mailbox or In-place Archive Mailbox option
8. Select create a New Folder option, provide a suitable name for the folder. (All data will store inside that folder) and Click on the Next button
9. Finally, provide Office 365 login credentials and click on Sign in to start OST to Office 365 migration process.
10. Once the process gets completed, check your Office 365 account.

Note: This functionality is available in business and enterprise licenses.

Other helpful features

• Convert OST file to PST, MSG, EML, and MBOX format.
• Import OST to Office 365 and Live Exchange Server
• Advanced search and filter options for selective conversion
• Free OST to Office 365 migration for the first 20 items per folder.

The Author

Deepak Singh Bisht

Content Lead |

Deepak Singh Bisht is a dedicated IT professional with over 9 years of experience, is a key member at SysCurve Software for the last 5 years. His expertise lies in email migration and data recovery, with a focus on technologies like MS Outlook and Office 365. Deepak, who also delves into front-end technology and software development, holds a Bachelor's degree in Computer Applications.

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