Word+-+If+word+automatically+changes+a+paragraph+style+when+you+make+changes+to+a+particular+paragraph

From: http://word.mvps.org/FAQs/Formatting/WholeDocumentReformatted.htm If you are a user of Word 2002 or above, you may have had this experience: you click in a single paragraph or select several paragraphs and apply italics, bullets, numbering, or some other type of direct formatting and the entire document (or at least more paragraphs than you had selected) becomes italic, bulleted, numbered, etc. If you press **Ctrl+Z** or click on the **Undo** button, the change is reversed for all but the originally selected text. What’s going on here?

The problem
If you look at the Undo list before pressing the button (by clicking the arrow beside it), you’ll see that the last recorded action is “Update Style.” Some styles in Word are set to update automatically. This means that if you change the formatting of one paragraph in the style, you change the style itself, and the change is applied to all other paragraphs in that style. This behavior is the default for TOC styles (the ones used for entries in a table of contents), and in that case it is very convenient because the TOC styles can be rather difficult to modify otherwise. Automatic updating can be helpful. For example, when you are creating a template and fine-tuning the styles, you may want them to update automatically so that you can immediately see the results of your experimentation with different formatting (once you’ve settled on the desired formatting for a style, you’ll disable automatic updating). And if you use appropriate styles for varying types of paragraphs, this behavior will not get out of hand. But if you use Normal style for most of your paragraphs and apply direct formatting to change the appearance of specific paragraphs, you absolutely don’t want Normal style behaving this way, yet many users of Word 2002 and above do experience this. It’s not entirely clear how the Normal style becomes set to “Automatically update,” but this seems to happen far more frequently in Word 2002 and above than in previous versions, and it seems likely that this problem, like many others in Word, is caused by a poorly written add‑in.

In Word 2007
Solving the problem is a bit more problematic in Word 2007 because the Modify Style dialog for the Normal style does not include the “Automatically update” check box. Consequently, if the Normal style acquires the “Automatically update” property, it can be reversed only with a macro, as follows: If the issue arises with a style other than Normal, it can be dealt with in the same manner as in previous versions. In the **Styles** group on the **Home** tab, click the dialog launcher (arrow in the bottom right corner) to open the Styles pane. Select the misbehaving style, click on the arrow to open the menu, choose Modify, and proceed as instructed above for other versions.
 * 1) Press **Alt+F11** to display the Visual Basic Editor. Press **Ctrl+G** to show the Immediate Window.
 * 2) Type:
 * ActiveDocument.Styles(wdStyleNormal).AutomaticallyUpdate = False**
 * 1)  Press **Enter**, and save the document.

Existing documents
Note that checking the “Add to template” box will ensure that new documents you create will not have the given style set to update automatically, but the style will not be changed in existing documents. You will have to repeat the steps above (except for “Add to template”) in existing documents that are affected.