OLM files are used only by Mac Outlook and can't be open in the Windows versions of Outlook because of the Windows version uses PST files rather than the OLM format. To open OLM files in Windows, you can open in it Outlook. but here is the best option you can Convert OLM file into Outlook PST on Mac OS. I will suggest you go for this Mac OLM to PST Converter, it is easy to use and one-click download, by this Software, you can easily convert your files without any type of problem or loss of data. For more information: toolscrunch.com/mac-ost-to-pst-converter.html