The lesson was worth the effort and encouraged Hoyos to make additional tweaks to his software to further ensure his systems didn't open a back door for hackers looking to pillage large corporate networks.

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"When I got a call from Lex to invite me in the back door he said he didn't think it was my cup of tea - which was a strange comment, " added Jefferies.

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"And when I looked at him, he looked back with this scared look and said, 'I can't hold this door shut, ' " said Ms. Brooks, wrapped in a green blanket inside the Moore Community Center.

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