"All it takes is one person you know, who you've sent an e-mail address," said Reshef. "This friend of yours has your e-mail address somewhere in his files, likely in his Outlook .pst file. He doesn't know P2P, and rather than share just some songs, sets the file-sharing software to share his entire hard drive, including his Outlook .pst file for spammers to find and see."Blue Security set up 500 new e-mail accounts and shared those addresses in several files on a PC connected to eDonkey 2000 and Gnutella p2p networks. Within a day they had received 100 pieces of spam, within three days it had increased to 300 spams and two weeks later each address was getting more than 100 spam e-mails a day..
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