WhiteSmoke

Awesome proofreading tool.
I originally bought it when I was applying for a University abroad and had to write an English application and essay.
This tools features:
1. Grammar, punctuation and writing style correction - but it doesn't automatically fix the mistakes but offers suggestions from which you can easily choose.
2. You can configure it to automatically check every mail you send from MS Outlook.
3. Spelling mistakes correction in 2 levels: 1. Regular, 2. Contextual.
4. Alers missing words or word repetition.
5. Bonus features such as: letter templates for different purposes, full text translation in a finger clique and a few more valuable stuff which I cant currently remember.
Bottom line: Very good software for students / editors / If you want your English to be flawless in general.

For years I was satisfied with White Smoke. I used the software for school. The. Program would stop working every year, but customer service reactivate the program. HOWEVER, this year, I was told they never had a life time service, and I would have to purchase a new yearly subscription to utilize my software. "We don't have it. We never had it." She kept saying the lifetime was the software, not the subscription. I don't think they advertise "life time" any more. But, buyers beware!