You can view emails, attachments, contacts, and calendars from a PST file without opening it in Microsoft Outlook by using MacSonik PST Viewer. The tool lets you open a PST file and preview its mailbox data, including email messages, attachments, contacts, calendars, tasks, and folder structure. It can be useful when Outlook is not installed or when you simply need to inspect the contents of an archived PST file. You can browse the available folders and review the stored data before deciding whether to export or convert it. MacSonik PST Viewer supports PST files created by different Outlook versions, providing a convenient way to access and examine PST mailbox data.