I have issues with Word 2013 Preview on my Surface RT tablet. When I create a document and try to directly share it to my friend via email, Word 2013 program says “There is no email program associated to perform the requested action.” But I have configured my Exchange mail and it works properly.
To send email from Word/Excel/PPT, office apps need a MAPI mail client to support and get them working. However, there is no Outlook available on Windows RT.
This is a big design miss. You can touch the File tab > Share > Skydrive, save it to Microsoft’s cloud and share with others. Or open an email message and insert the documents as attachment.