One of the anoying things about Microsoft is that they allways want to their own thing, instead of following a standard. It is what happened to the internet browser (the successful inernet explorer challange of netscape) and the ebook reader (Microsoft Reader failed to beat Adobe (Acrobat) Reader), to name two. 

Often these new apps come with their own file name extension, making them incompatible with other software. Now they actually have one format where they are the absolute standard . I think at the moment every pc in the world is able to process a .doc file. Even if you dont have MS word, most alternative software will process .doc files, online word processors are keen to have an import feature, google search indexes the files and even windows “native” wordpad can open a .doc file. So Microsoft got bored with people having to much ease of use and decided to through the .docx extension at the world in Office 2007. To maximize annoyance they made it the default format to save files in. Suddenly i found my inbox cloaked with unreadable files. Google Mail didnt have previews and nothing on my pc would read it. The only option was to find equally annoying free online converters, or - best one, but not always appropriate - send it back. 

Luckily Zoho- the online office suite - had a response . They launched import functionalatity for Docx for their Writer app.  So no more annoying converters. And while you’re at zoho, have a look around.There is a lot to see!