Follow the steps to convert OLM file to MBOX on macOS Monterey:
Step1: Download and Open MacMister OLM to MBOX Tool on macOS Monterey.
Step2: Utilize Add File(s)/Add Folders property to add individual OLM files and the entire folder with multiple OLM files on the software. Click Next.
Step3: Verify the OLM files that are listed on the application and hit Next button.
Step4: Choose MBOX saving type from Select Saving Option.
Step5: Set sub-options of MBOX format and click on Export.
Step6: Now, check the current export status of OLM file appearing on Live Conversion screen.