An e-mail sent by the cabinet secretary, Sir Gus O’Donnell, told civil servants to ensure the ban was communicated throughout their organisations.
The move follows defence secretary Des Browne’s announcement that an investigation would be launched into the theft, earlier this month, of a laptop containing information on 600,000 people looking to join the armed forces.
Earlier, Browne revealed that a Royal Navy laptop containing the personal details of potential recruits had been stolen from an official’s car in 2006 and that, in 2005, another went missing from a recruitment centre in Edinburgh.
The latest laptop to go missing included detailed personal profiles of around 153,000 people, including passport details, NHS numbers and driving licence details.
“For around 3,700 people, banking details were also included,” Browne said.
None of the data was encrypted.
Browne said an inquiry into MoD information security procedures would be undertaken by Edmund Burton, chairman of the Information Advisory Council, who served in the armed forces for 38 years.
Shadow defence secretary, Liam Fox, said the data loss was potentially more damaging than HMRC’s loss of 25m child benefit records and that it showed “incompetence, mismanagement and poor procedures”.
