Bought a software online which claimed to be able to check plagiarized essay. It did not work at all, and I have not received any refund although they have the guarantee policy.

Don't try it.

I used Eve too - bought it but didn't like it at all; requested a refund and after a few emails back and forth they refunded my money. Anti-plagiarism software is a waste of time - it will not provide a precise answer. It will just list dozens or hundreds of sites that have the words that are in the original document. In the end when your paper contains "hello, how are you doing today?" (for example), it will mark it as plagiarized because some other millions of pages contain the words: "hello, how, are, you, doing, today". In the end it will mark your document as 70% "plagiarized" even though it's not plagiarized at all. This software is as stupid as it gets.

My school requires us to scan all papers through Turnitin.com. In my opinion this does not and will never work well. There are more and more papers in their databases; that's why their system is getting more and more useless. Some of my friends (actually, me too) got busted because of that. Fortunately the teachers know about the weakness of this system too and they turn a blind eye on the plagiarism scan results. Then - why do they use it at all? I've heard it costs pretty much money to scan each paper. IMO that money could be spent on some more useful resources.

What?!!?? What do you mean "requires"? It's like your teacher told you "you must buy a X brand laptop to use on my course; otherwise I'll fail you". Turnitin sux and they use your copyrighted work to cash in. Then they store your papers forever to "compare" results of other works with your work. How much commission do they pay you??

Teachers are lazy and think they can "require" the student to do the job for them. What kind of world do we live in?

Forgot to add - I wonder who's "great" idea it was but it was "smart"... As far as I know teachers require the students to submit papers to Turnitin THEMSELVES. Then, when there's a problem, they think they will not be liable for the copyright infringement.. because the student - not them - submitted the paper to the turnitin system.

Smart...