Why can Apple Mail Not Open an OLM File?
Outlook for Mac stores archives as OLM files. Apple Mail imports mailboxes in Apple Mail or mbox format, as Apple documents.
So the file needs a format conversion before you import OLM data into Apple Mail, and Apple Mail reads that conversion Apple Mail can read it.
| App | File format |
|---|---|
| Outlook for Mac | OLM |
| Apple Mail | Mailbox packages in .mbox format |
| Thunderbird | MBOX |
Do You Need a File at All?
Method #1: Sync a Server Account (Free)
Who it suits. Users whose mail sits on an IMAP, Exchange or iCloud server. Extra application. None.
Add the same account to Apple Mail and the server mail appears there. This works only for mail that lives on the server. Mail that sits only in a local OLM archive needs the next method.
How do You Export OLM Data as MBOX and Import It?
Method #2: Convert OLM to MBOX (Paid After Demo)
Who it suits. Users with local OLM archives. Extra application. OLM Converter.
The OLM Converter for Mac exports OLM data to MBOX, EMLX, PST and other formats. It previews items, filters by date and splits large output. It reads OLM files from Outlook 2011, 2016, 2019 and 2024.
- Install the converter and select the OLM file.
- Choose MBOX as the export format.
- Select a destination folder and select Export.
- Open Apple Mail and select File, then Import Mailboxes.
- Select Files in mbox format and Continue.
- Choose the MBOX file or folder and select Choose.
Apple Mail places the messages in a new Import mailbox. Drag folders and messages to your own mailboxes, then delete the Import mailbox. The trial converts 100 emails per OLM file.
What should You Check After the Import?
- Compare message counts with the Outlook folders.
- Open messages with attachments.
- Check calendar and contact needs separately, because MBOX holds mail only.
Our OLM file guide explains the format, and the guide to export OLM as MBOX adds more detail. Moving to Windows instead? Read how to convert OLM to PST.
Frequently Asked Questions
Can Apple Mail Import an OLM File?
No. Apple Mail imports Apple Mail and mbox format. Convert the OLM file to MBOX first.
How do You Import an MBOX File Into Apple Mail?
Select File, then Import Mailboxes, choose Files in mbox format and select the file or folder.
Where do Imported Messages Appear?
Apple documents a new mailbox called Import. Drag folders and messages to other mailboxes.
Do You Need a Converter for Server Accounts?
No. Add the account to Apple Mail and the server mail syncs.
Which Outlook Versions does the Converter Read?
The vendor page lists Outlook 2011, 2016, 2019 and 2024 for Mac.
Does MBOX Store Calendars and Contacts?
No. MBOX holds mail. Export calendars and contacts in other formats.
Is There a Trial Limit?
The Mac trial converts 100 emails and 25 category items per OLM file.
Author's Verdict
Sync server accounts when you can, because it needs no conversion.
Convert OLM to MBOX for local archives and import with Apple Mail.
Key Takeaways
- Apple Mail reads MBOX, not OLM.
- Server accounts sync without a file.
- Apple Mail files imports under an Import mailbox.
Related Guides