Well, I usually do not use other than the spell/grammar check in the software that i am using - but I have heard about GINGER software which they say is very good.
Just use Microsoft Word to point out possible errors. Do not follow it slavishly. No software will eliminate all grammar and even spelling errors automatically. Get an English First Language speaker to help you.
I agree with Ian that the spelling and grammar checker in MS word is pretty good, although I do not always agree with it. A native speaker is also a good option, if you can find one. But it should be a native speaker who is experienced in academic writing.