Striata Reader - Open with dialog box
When the I try to open the encrypted Document, a dialog box appears asking which program to use to open the document.

Explanation
When this happens (and it can happen for other programs too) it means that you haven't installed the Striata Reader correctly. It indicates that Windows cannot find the Striata Reader, and is not sure what to with the attachment. So it asks you to choose.
Solution
The best thing to do is to download the Striata Reader - again if necessary (make sure you have the right one by going here). Follow the instructions from the download site.
Open the attachment once you have downloaded and the installed the reader.

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