That's controlled by Tools - Options - Edit - Keep track of formatting.

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Herb Tyson MS MVP
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"Robert Halford" wrote in message
...
In Word 2003 if I make a change to a style Word automatically adds it to
the style list - for example "Heading 1 + Italic" or "Normal + Bold" - how
can I stop Word doing this?

Someone said check the "Prompt to update style" checkbox in the edit
options, but this doesn't work.