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Updated: February 28, 2025

.OLM File Extension

There is only one filetype that uses .OLM file extension and it is Mac Outlook Database File.

Mac Outlook Database File

File category: Data Files
Developer: Microsoft
Open with: Aryson OLM Converter
Platforms: Windows, macOS, Linux

An OLM file (commonly understood to mean Outlook for Mac) is a data file used by Microsoft Outlook for Mac to store various types of user information. It can contain email messages, contacts, calendar events, tasks, notes, and other mailbox data. This format is specific to Outlook on macOS and cannot be opened directly by the Windows version of Outlook, which uses PST files instead. Microsoft introduced the OLM format in Outlook 2011 for Mac.

OLM files are used to save and organize Outlook data locally on a Mac. Users can export their emails, contacts, and other information to an OLM file for backup purposes or to transfer data between Outlook installations on different Mac computers. A single OLM file can contain multiple folders and subfolders, maintaining the structure of a mailbox.

How to Open .OLM as Mac Outlook Database File

OLM files can be opened in Microsoft Outlook for Mac and Microsoft Outlook 365 (on Mac devices). They are not compatible with Outlook for Windows without conversion. To open an OLM file on Windows, you need to convert it to a PST file using specialized tools like Aryson OLM to PST Converter or Aspose.Email. If an OLM file is corrupted, repair utilities such as Stellar Phoenix OLM Repair can help recover lost data, including emails and attachments.

Applications That Open OLM Files

Windows Apps for OLM Files:

macOS Apps for OLM Files:

Linux Apps for OLM Files:

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