You can import PST files to Office 365 using Microsoft's supported import process or a dedicated migration tool. The Aryson PST to Office 365 Migration Tool provides an alternative for transferring PST mailbox data. Before choosing a method, review your mailbox size, account permissions, and migration requirements. After importing, verify emails, attachments, and folders. To Know More: https://www.arysontechnologies.com/blog/how-to-upload-pst-into-office365/