When you right click inside Windows Live Writer interface, you see one extra unfamiliar option known as Paste Special. Most of the bloggers don’t use this option generally.
Text editor applications such as Microsoft word use some kind of special markup language to display text on the screen or printout of the document. The markup language comes into action as you bold the text, underline it or change its position. But when you publishes the same text on internet, its format don’t retain as it conflicts with HTML and CSS language of the webpage. Due to this conflict it is advisable to remove all the formatting before publishing the webpage. Paste Special do the same.
If you the one who prefers to write article on MS Word application and then copy it into Windows Live Writer then instead of pasting it, right click on the live writer interface and select Paste special option.
A windows will pop up asking you to choose one option among three given options. The default one is Thinned HTML and you don’t need to change it because it removes all the unrecognizable HTML markup formatting. Thinned HTML removes all the extra formatting and optimizes the text to fit best on the webpage and you won’t find any conflict on the page. Avoid using the last option, i.e. Keep Formatting because it maintains all the formatting including those which can make your web page look ugly due to mark up languages conflict.