The spelling and grammar checker isn't working as expected
Sometimes you may want the spelling and grammar checker in your Office program to ignore certain spellings or grammatical constructions. In other situations, you may not know why the grammar or spelling checker is flagging, or not flagging, some text.
Cause why your Spell Checker is not working
This may occur for any one of the following reasons: Proofing tools are not installed. The Speller EN-US add-in is disabled. The Do not check spelling or grammar check box is selected. Another language is set as default.
Here are some suggestions to try when the spelling and grammar checker isn't working as expected or you want to customize your results.
Ever have one of those days where you’re trying to get out an important document, but you find that Microsoft’s Word spellchecker isn’t working? Sometimes you can’t check a specific document and other times you can’t spell-check any documents. Either way, you might try some of these suggested solutions.
Spell Check Doesn’t Work for a Specific Document
There are times you’ll find Word’s spell check just won’t work for one document. You can open other files and spell check works. In these instances, the problem probably resides with the selected document language or formatting.
How to prevent this happening again
be leisurely in your closing down (powering off or hibernating) of the computer after properly closing your OO file and OO. Use the formal computer closedown procedure and wait for a few seconds before powering off to be certain all disk activity has ceased - damage to the spellchecker often occurs if the computer is powered down before the hardware/software write buffers have flushed. It is only a matter of a few seconds - these few extra seconds will be less than the time needed to correct the problem, or, more likely, to rebuild a damaged file which can also occur through such over-hasty shutdown.