If you have both Outlook for Mac and Outlook for Windows installed on your computer, you can export the OLM data from Outlook for Mac and then import it into Outlook for Windows to convert it to PST. Here are the general steps:
1. Open Outlook for Mac.
2. Click on "File" in the menu bar.
3. Select "Export" and choose the items you want to export (such as emails, contacts, or calendar).
4. Choose the destination where you want to save the exported OLM file.
5. Copy the exported OLM file to a Windows computer.
6. Open Outlook for Windows.
7. Click on "File" in the menu bar.
8. Select "Open & Export" and then choose "Import/Export".
9. Choose "Import from another program or file" and click "Next".
10. Select "Outlook Data File (.pst)" and click "Next".
11. Browse to the location of the OLM file and select it.
12. Choose the desired options for importing and click "Finish".
If your manual mathod faild to convert OLM to PST, then you can try third party Kernel for OLM to PST Converter tool. Get more information, visit to: https://www.nucleustechnologies.com/olm-to-pst.html