iPhone & iPad guide
How to Open Winmail.dat on iPhone or iPad (5 Steps)
Tap the winmail.dat attachment, open the Share menu, and choose Winmail File Viewer to view, save, or share the Outlook files inside.
Free message viewing · Purchase required for attachments
Open winmail.dat in five steps
- Install Winmail File Viewer from the App Store.
- Open the email in Mail, Gmail, or Outlook, or find the saved attachment in Files.
- Tap the winmail.dat attachment to open its preview.
- Tap Share and choose Winmail File Viewer. If it is not listed, tap More.
- View, save, or share the extracted documents and images.
Why did I receive winmail.dat?
Outlook can package a message and its attachments into a Microsoft TNEF container, which reaches other mail apps as winmail.dat. The original files are usually still inside.
What is a winmail.dat file? →Other ways to open it
Read the message free in the online viewer, or ask the sender to resend the files with HTML or plain-text email instead of Outlook Rich Text.
How to prevent winmail.dat
Ask the sender to switch from Outlook Rich Text to HTML or plain text. Corporate senders may need their email administrator to change TNEF settings for external recipients.
Frequently asked questions
Can I open winmail.dat on iPad too?
Yes — the same steps work in Mail or Files on iPad.
Does this work with Gmail or Outlook on iPhone?
Yes. Use the attachment’s share menu, or save it to Files and share from there.
Do I need to pay?
Message viewing is free. A subscription or credits are required to view and save attachments; see the App Store listing for current prices.