I'm using C# to create an outlook addin, but can only retrieve the email in plain text or HTML format. I know you cannot retrieve RTF format (without going through the hassle of word documents). However, my problem lies in the fact that I need to be able to convert the HTML into XHTML so that it can be consumed by SharePoint. Is there advice that would be useful for me to do this. I'm thinking of using regular expressions but I'm not sure of the what the Regex would be. Any suggestions? Maybe outlook has a method which makes something like this easier?