Some end users may require their Exchange mailbox to be moved to their own Office 365 account. They can do this job by themselves. It is done by exporting the user mailbox to PST from MS Outlook and then importing the PST file to Office 365, again from MS Outlook.
The feature to export data to PST is available in desktop versions of Outlook. However, the steps vary slightly in different versions of Outlook.
In Outlook 2016/2013, to export data to PST file select the File menu from the ribbon, and then click Open & Export > Import/Export. In the Import and Export Wizard, select Export to a file and then Outlook Data File (.pst). Also, you can select the required folders, filter the data (use the Filter button), and browse for the saving location. To export Exchange mailbox to PST file steps are shown in the diagram.
Note: In Outlook 2010, go to the File tab and select Options; in Outlook Options, select Advanced. Now, under the Export section, select Export. In the export wizard, you can follow steps similar to those given in the diagram to export Exchange mailbox to PST file.
Now use the desktop version of Outlook to login to the Office 365 account. To import the PST file, select the File menu from the ribbon, and then click Open & Export > Import/Export. In the Import and Export Wizard, select Import from another program or file and then select Outlook Data File (.pst). Now browse for the PST file, and select the folder to which the PST file is to be imported. For the steps, see the diagram.
Using the PST Export/Import method, end users can move their own mailboxes to Office 365. This method is simple and straightforward, and works with all recent versions of Outlook. However, an easier method is to use professional tools like Kernel Import PST to Office 365 that can import OST (and PST) files directly to Office 365. Meanwhile, Exchange administrators can use third-party EDB to PST converter tools like Kernel for Exchange Server to move many Exchange mailboxes to Office 365 very quickly and directly.