If you're trying to access an OST file on your Mac, you've likely already discovered that macOS offers no native way to open this format. OST files are Microsoft Outlook's offline storage files created on Windows, and they simply don't work on Mac out…

Short answer — yes, absolutely! MSG is Microsoft's proprietary email format that Gmail, Apple Mail, and Thunderbird simply cannot open natively. Most people assume installing Outlook is the only option, but that is completely unnecessary in 2026.…