Word 2003 Not spell Checking

I got this from:

http://domino.lancs.ac.uk/pub/usghelpdesk.nsf/0/DF1B055703F6261A80256F8F0045EA6C?OpenDocument

>Text Does Not Spell Check - Word 2003
(and possibly Xp Word 2002, 2000, 97)

If the spell checker passes over areas of text and does not pick-up mis-spelt
words it is possible that the text has been marked not to be checked.

To solve this problem do the following:
1. highlight the area which won't spell check.
2. click 'Tools' menu then the 'Language' option, then 'Set Language' option.
3. ensure that 'Do not check spelling or grammar' option is NOT selected.
4. click

The Spell Check should check the area now.
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With me the case was that this option was selected, but Word was still not spell checking. To solve this, check the 'Do not check spelling or grammar' box, hit ok, and then do the same again and uncheck the box. All fixed.