Windows tablet 8.1 unable to open attachments; some headers garbled
Microsoft has put together a great page on troubleshooting email on their Surface tablet. You can access that page at http://www.microsoft.com/surface/en-ca/support/email-and-communication/troubleshoot-mail.
If email attachments aren't opening properly, they advise checking to see which app you are using as your default. Do you have the email app set as the default or is there a different program set instead?
As per Microsoft's instructions on setting the default app -
To open the defaults page
Swipe in from the right edge of the screen, tap Settings, and then tap Change PC settings.
(If you're using a mouse, point to the upper-right corner of the screen, move the mouse pointer down, click Settings, and then click Change PC settings.)
Tap or click Search and apps, and then tap or click Defaults.
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