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I have Microsoft Office 365, which contains the latest version of Word ( equivalent to Word 2013). I have looked through all the Style sets, and there are none with Heading 3. I know what you are referring to. There definitely was a Heading 3 on earlier versions of Word. I have Word 2000, which has it.
All I can tell you is that it must have been discontinued when the menus were upgraded to ribbons, which I think happened with your version of Word 2010.
I hope that this information helps. Can you tell me how you are able to even try to change, for example, Emphasis to Heading 3, when Heading 3 is not visible or grayed out?
Wait! Reset the above information. I just found Heading 3. It is under the fourth style set, which is named Basic (Stylish). It was not there the first time I looked. I will get back to you with more information, when I discover what I did that revealed it. In the meantime, please answer my question above. It will help me to understand your Word environment.
OKAY! I'VE GOT IT. THIS IS SO SIMPLE THAT YOU WILL NOT BELIEVE IT.
You do not have to go to Design view at all. Just open a document and stay on the Home ribbon menu. Under Styles you will see Normal, Heading 1, Heading 2, Title, Subtitle, etc. Click on Heading 2, and Word will create Heading 3. Click on Heading 3, and Word will create Heading 4, etc., etc., etc.
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