Summary: Outlook for Windows creates OST files, while Outlook for Mac supports OLM format. This format difference often causes issues when users want to access old or orphaned OST emails on Mac. In this guide, we'll explain the best way to import OST emails into Outlook for Mac without losing attachments, contacts, or folders.

Why Can't You Directly Import OST into Outlook Mac?

OST (Offline Storage Table) is a Windows Outlook data file, while Outlook for Mac only supports OLM files. Since both formats are different, Outlook Mac cannot directly read or open OST files. That's why conversion is necessary.

Manual Workarounds (and Their Limits)

Export Mailbox in Windows Outlook: You can export OST data into PST if Outlook is connected. But Outlook Mac still won't import PST files directly.

Exchange/Migration Setup: Requires both environments configured, which is not practical for orphaned or inaccessible OST files.

Drawback: Time-consuming, requires technical knowledge, and may not work for corrupted OST.

The Reliable Method - Use an OST to OLM Converter

The most effective way is to use a professional tool like Advik OST to OLM Converter. It converts OST files into OLM format in just a few steps, making them fully compatible with Outlook for Mac.

Steps to Import OST Emails into Outlook Mac:

Download and install Advik OST to OLM Converter.

Launch the tool and add your OST file.

Select the OLM format as the output option.

Choose the destination path and start the conversion.

Open Outlook for Mac and import the converted OLM file.

Key Benefits of This Method

Preserves folder structure, attachments, and metadata.

Supports orphaned, damaged, or large OST files.

Works with Outlook 2021, 2019, 2016, and Mac versions.

Saves time compared to manual workarounds.

Final Words: The best way to import OST emails into Outlook for Mac is to first convert OST to OLM using a trusted tool like Advik OST to OLM Converter. This ensures complete migration without data loss.