Open 📎 Winmail.dat, MSG, EML and MHT files easily and securely Letter Opener has always been the perfect app to open Winmail.dat and MSG e-mail files—the format used by Microsoft Outlook and Exchange—and also internet standard EML email files. And it’s even easier and more secure with Letter Opener for Android. Your files are never transferred or shared when you use Letter Opener, and your files and content stays protected on your device. Privacy and security Privacy and security aren’t just something you should hope for—they’re something you should expect. That’s why we never transfer or shared your files. Everything is done on your trusted device. Your emails stay your business. Supported file types: • winmail.dat or AT00001.dat • Outlook messages: .MSG • Outlook templates: .OFT • E-Mail files: .EML, .EMLX • Web archive files: .MHT, .MHTM, .MHTML Made with a special 😤 for winmail.dat files.