To convert an OLM file to PST, export your Outlook for Mac data to an OLM file, then move it to a Windows PC. Install Outlook for Windows or a reliable OLM to PST converter tool. Import the OLM, preview mail, contacts, calendars, and export to PST. Finally, open the PST in Outlook via File > Open & Export > Open Outlook Data File to access all items safely without data loss and with folder structure intact.