.docx is the extension for Microsoft Word 2013 documents. In fact, the .docx extension was first introduced when Word 2007 was released, so Word 2007, Word 2010 and Word 2013 use it. The .doc extension, on the other hand, is used by versions of Word that came before 2007. Every new release of Word brings us new features that don’t exist in the last version. This means that .docx documents may contain features not supported by versions of Word prior to 2007.
One way of getting round this problem is to convert docx to doc. If you convert your docx documents to doc, then you know that everyone who opens them will be able to see the full glory of your content.
If you are the author of a .docx document, then you must already have Word 2007, Word 2010 or Word 2013. This makes the conversion task much easier, as those versions of Word can do the conversion to doc for you. For ease of illustration, let’s look at how you do this in Word 2013. Open your docx document in Word 2013 and then click the File tab > Save As . For this example, let’s just save the document to our computer, so ensure that Computer is selected, and click browse.
When the Save As window opens, make your way down to the “Save as type” selector and choose Word 97-2003 Document (*.doc).
To avoid confusion, I would keep the new file name the same. It will be much easier to understand if you have two documents with the same name but different file extensions than two differently named documents. In the case of our documents, they are obviously the same document, but in different formats. Find an appropriate location on your hard drive and click Save. Again, I would keep things simple and save your new doc document in the same place as your original docx document.
You now have two documents, one with a .docx extension, and the other with a .doc extension.