format c: works good as well, but its a pain. some of that malware is pretty nasty when it gets in, it can be pretty much impossible to get it out with out wiping your disk. the reason kaspersky did not remove it is probably because it embedded itself in a system file or made itself look like an important windows file or something, who knows. in any case, don't rely solely on anti-virus programs, get a firewall as well if you don't have one already and be sure to keep all your anti-malware programs up to date.
i have always used AVG, so I don't know about kaspersky, but AVG will allow you to quarantine files so they can't be copied or executed, i guess if for some reason you couldn't block it or remove it. in any case, you could always stick with more 'reputable' porn sites in the future

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