Hall told a congressional panel earlier this year that she was threatened with jail if she revealed information about the missing messages.

CNN: White House begins copying tapes of missing e-mails

The White House, with the aid of contractors, will have to go back through those tapes -- perhaps six months worth -- to extract the missing e-mail messages.

CNN: White House officials say e-mail problem was not a high priority at end of 1999

He said the pain of the Dowler family had been "trebled" by the hacking of voice mail messages of their missing teenage daughter, Milly, who turned out to have been murdered.

CNN: STORY HIGHLIGHTS

The revelation that the girl's phone had been hacked after she was reported missing in 2002, and that messages were deleted, giving her parents hope she was alive when she had already been murdered, outraged Britain this week.

CNN: Murdoch's scandal-hit News of the World to shut down

These individuals are the same ones who are checking email, sending messages, signing vital contracts, and more, all without missing holiday festivities.

FORBES: U.S. Is On Cloud 9 When It Comes To Competition

In a month-long experiement, morning register at Friars School in Bangor is being scanned into a computer and automatic personalised messages sent out to the mobile phones of parents whose children are missing.

BBC: Parents face truancy warning