Via Facebook, The Melt offered a secret password to fans of the sandwich shop.

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Virdi admitted he could not explain how the letters had been produced by a user at Hanwell Police Station using his own secret password.

BBC: Gurpal Virdi

But Passport, which stores personal information on Microsoft's servers, still lets customers use wildly insecure passwords like "password, " and lets anyone who knows your zip code take several cracks at guessing the personal "secret question" that resets the password.

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But if users only have one password to keep secret, they're likely to choose something much harder to hack (an obscure mix of letters and numbers, for example), and to keep it a better secret.

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Since the inaugural "First Listen, " a nod from the series has become such a plum that NPR Music keeps record-label submissions in a secret computer file, accessible only to employees who have the password.

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He also advised adopting two-step authentication, which involves a personalised "secret number" allocated to users in addition to a username and password, and ensuring that the latest version of Wordpress is installed.

BBC: Wordpress website targeted by hackers

"You will not share your password, (or in the case of developers, your secret key), let anyone else access your account, or do anything else that might jeopardize the security of your account, " the agreement reads.

CNN: Doug Gross,

We recently had our annual pay increase exercise at my university and it did a number of things, including hand delivering pay worksheets and emailing password-protected Excel spreadsheets to ensure that the amount of the raises given was a well-kept secret.

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