When I center text, the whole page is centered.

[Bold]

I recently re-installed Office. Since then I am having formatting problems.
When I attept to make bold a word, the whole text is also made bold. Same for
centering.

I can solve it by saving the document as a text file and re-opening it.

 

[Suzanne S. Barnhill]

See http://word.mvps.org/FAQs/Formatting/WholeDocumentReformatted.htm