[vsoler]

I am writing a long document (some 30 pages) and I happen to use the
Table of Contents feature through the use of styles. This works fine.

However, when I happen to format some lines using a format (for
exemple, centered + bold) that is very similar to ones of the heading
styles ("Heading 1", for example), Word changes the style
automatically to "Heading 1", and I want to avoid it.

Could anybody help by saying what option exactly I have to switch off?

Your help is highly appreciated.

Vicente Soler