If you use a MAC and MAC Mail to manage your e-mail, you may send attachments to Microsoft Windows users and they are unable to read those attachments. The problem is that the attachments are not being encoded by MAC Mail in a way Windows users can read them. From the MAC Mail "Edit" menu, you need to choose "Attachments" and the option "Always Send Windows Friendly Attachments." With that option set, both MAC and Windows users will be able to read your attachments. The default way that MAC Mail ships only encodes attachments so that MAC users can read them.

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