Had I not

[jack]

http://www.quepublishing.com/article...63735&seqNum=2

1. Had I not found this free tool, I probably would have failed in my data-recovery attempt. (Is this sentence correct?)

Should it be like this?
2. If I had not found this free tool, I probably would have failed in my data-recovery atttempt.

Or like this:
3. Had I not found this free tool? I probably would have failed in my data-recovery attempt.

Thanks.

[Tdol]

Had I not found.... is an alternative way of saying #2- it isn't a question, it's inversion. It's used quite a lot in third conditional sentences.

[jack]

Had I not found.... is an alternative way of saying #2- it isn't a question, it's inversion. It's used quite a lot in third conditional sentences.

Why is that? Is that the shorthand of saying it? That is not a standard right? For essays, you shouldn't use that right?

[Tdol]

It's actually a formal use, so it's fine for essays. Remove 'if' and invert the verb. It can sound more emphatic, so feel free to use it.

If I had been there, things would have been different.
Had I been there, things would have been different.

Use them both.