Archiving Outlook emails to an external drive as an OLM file can be done manually, but it does require a few steps. If you're using Outlook on Mac, go to File > Export, then choose to export Mail, Contacts, and Calendar items to an OLM file. Once the export is complete, you can simply copy the OLM file from your Mac’s local drive to your external hard drive. Just make sure the external drive is properly connected and formatted for Mac use.

However, if you're looking for a faster, smoother, and more reliable experience—especially when dealing with large mailboxes or multiple exports—the Aryson OLM Converter Tool is a great option. It not only helps you create OLM files efficiently but also offers the flexibility to convert them into other formats if needed. It's ideal for users who don’t want to risk data corruption or waste time on complicated manual steps.