Do I use a spell checker? Absolutely. Would I rely on it to help me craft an important document? Absolutely not.
And there are several reasons why. Hear is just won of them.
Don't get me wrong, I am not against using them. Your spell checker will catch some typos or spot a word used twice. And for those reasons, they are worth using. But it's important to note the downside of relying on them exclusively.
One thing I find frustrating is that spell checkers don't speak Canadian (although they can be taught). For us, writing is a labour of love. For our southern neighbours/neighbors, it is a labor of love. And if I've learned anything about my readers, it's that while they may like Americans, they sure don't like the way they spell.
(And, as someone recently pointed out to me, "Microsoft may be good at a lot of things, but the English language isn't necessarily one of them.")
And what about grammar checkers? Those, we don't use at all. At Adams Jette, we rely on professional proofreading and having all our documents edited in-house before they go out. Unlike spell checkers where a word is either right or wrong, grammar is open to interpretation.
As a long-time member of the Editors' Association of Canada, I have it on good authority that just when you think you know an English-language "rule," there will be five editors ready to point out 27 exceptions.
So, how do you ensure proper spelling and good grammar? The easiest thing to do is to give your text to someone who has never seen it before. That "fresh set of eyes" is likely to see things you don't.
Even better, have your important documents--that is, any document that is seen by anyone outside your office--edited or proofread by a professional.
If that isn't possible, I would suggest you pick up a copy of Karen Elizabeth Gordon's book, The Deluxe Transitive Vampire: The Ultimate Handbook of Grammar for the Innocent, the Eager, and the Doomed." Written with a style that will make you smile, if not openly chuckle, Ms. Gordon covers grammar in a way that makes it--dare I say it?--enjoyable. This book should be a high-school textbook.