If you need an effortless way to
import PST files to a shared mailbox in Office 365, I recommend trying
Yota PST Converter. It is user-friendly and does not require Outlook. You can import PST files of any size without data loss, including emails, attachments, contacts, calendars, and more. It also maintains the folder hierarchy and original formatting during migration. The tool supports all editions of Outlook and works on all versions of Windows. Ideal for both personal and business needs when importing Outlook data into Office 365 shared mailboxes.