Do you want to open OLM files in Windows Outlook? MacSonik OLM Viewer Pro helps you open OLM files in Windows Outlook. Even this tool opens the OLM file without installing Outlook. This tool is free for unlimited viewing and also allows you to convert an OLM file to multiple file formats, like  PST, MBOX, CSV, EML, and PDF. The demo trial allows the user to convert 50 emails per folder. Overall, it is the best tool for opening OLM files on Windows Outlook.