It appears that the company placed a copy of the game on its public server, under password protection, for select reviewers to download and try out.

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Resetting the preferences in the e-mail client to the ISPs mail server will fix the problem, but will disable protection by Poproxy.

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Rarely are leaks intentional: Somebody at work might post a file on a server to download at home, a wrongly configured server might make too much of a hard drive searchable or a Web site's password-protection might be flimsy enough to be accessible to search engines.

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