Dotx and dotm files are similar to docx and docm files in that the "X" in the file extension stands for xml, and the "M" stands for macro. (A macro is a program that is embedded in a Word file used to automate repetitive tasks.)
However, there is a difference between the dot twins and their "docx" cousins...you cannot open them unless you have Word 2007 or Word 2010 installed.
Let's take a minute to discuss what these files are and why they are so useful.
(Unless stated otherwise, information in this article applies to both file types.)
A "dot" file is a special type of Word file. As in all previous versions, the .dot* in the file extension indicates the file is a Microsoft Word template.
Template File Quick Facts
When you open a template file, you are opening a copy of it. Any changes you make to the copy are saved to the new file, not to the template.
Template files save time. If you find yourself recreating the same document over and over with just minor changes, create a generic form of the document and save it as a template file. Then, when you create a file based on that template, most of the work is already done!
Why save as a dotx instead of a docx file? Because as mentioned previously, when you open a template file instead of a regular Word file, it opens a copy, not the template itself. This protects your template from unintended changes.
Every time you create a new file from your template, it is a brand new file, ready for you to modify as needed.
There are several ways to open template files. How you open the file depends on what you want to do...start a new file based on the template, or edit the actual dotx file.
To start a new file based on a template, follow these steps:
If you know where the template file is located, an easier way to start a new file is to browse to the template file, then double-click it. A copy of the template will open in Word 2007.
Use an Existing File
You can use an existing file as a template. Follow the same instructions as Starting a new file based on a template, but under step 3, select New from existing. Then browse to the file and select it. When you click Create, a copy of the file will open. Then you can modify it without changing your original file.
If you want to create a new template based on another template, follow the same instructions as Starting a new file based on a template, but under step 5, select Template, then click Create. This creates a new dotx or dotm file.
If you want to edit the original template, follow these steps:
Only new files based on the template will show your changes. (Old files will need to be edited individually.)
You can create a template from any Word file. To save a file as a template file, follow these steps:
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