Mac Outlook OLM files cannot be opened in Windows Outlook directly because Outlook for Windows only supports PST format. To access OLM data on Windows, you need to convert the OLM file to PST first. Manual methods like IMAP syncing are slow and may not transfer contacts or calendars properly. A reliable solution is to use a professional tool like DataVare OLM to PST Converter. It safely converts OLM files to PST format while preserving emails, attachments, folders, and other mailbox items. After conversion, the PST file can be easily imported into Outlook using the Import/Export option.