Letter Opener

The winmail.dat solution

Some people still use Outlook. And whenever they send you something like an attachment or appointment, it shows up in your Mail with a winmail.dat file attached. (Ugh.)

But Letter Opener seamlessly converts all types of Outlook’s irksome winmail.dat files. (Hooray!)

Letter Opener Lite — Try it for free

The free version lets you see sender, recipients, subject and message text of winmail.dat attachments.

Winmail.dat Premium Add-on — Available within the app for only $9.99 give you access to:


Get files which have been attached to an Outlook message.


View embedded e-mail messages.


Preview contacts with QuickLook or import them into Contacts app.

Quick Look

Quickly view the contents of a winmail.dat file without opening it or starting an application.


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Get more than the occasionally winmail.dat file?

Letter Opener Pro seamlessly and automatically converts winmail.dat files right inside your OS X Mail application. With Letter Opener Pro the attachments appear like any others!

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Get the power of Letter Opener on the road!

Get full-featured winmail.dat viewing power for iPhone & iPad that doesn't feel like you left some important features back at the office.

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