In Microsoft Word, why does formatting selected text result in whole document being formated?

Question

Sometimes when I select a piece of text and apply some formatting to it, the whole document changes to that format. What am I doing wrong? If I undo, I get the desired result, ie only the selected text gets the formatting.

I'm using Word 2003

Answer 1

It is possible to change the formatting for a style instead of for the text you are interested in. If you do this, all text with that style (possibly the entire document) will change.

If you inappropriately mix styles in your document, this can result in some very strange results.

Answer 2

If an undo fixes it, it's possible you are doing the format twice (once on the selection once on the whole document). Are you using hotkeys or menus?

Answer 3

Its simply a bug. Install Office 2007 or 2010 and your workflow will be much easier.