Computers are giving away secrets of previous owners

The trade in second-hand computers could be giving fraudsters access to sensitive personal and financial information, research has found. Details of a married woman's affair, national insurance numbers and confidential company data were on the hard drives of computers sold on eBay.

The trade in second-hand computers could be giving fraudsters access to sensitive personal and financial information, research has found. Details of a married woman's affair, national insurance numbers and confidential company data were on the hard drives of computers sold on eBay.

Despite efforts by the previous owners to wipe the memories, experts discovered more than half of the computers examined still contained personal data. The University of Glamorgan acquired 92 hard disks from the popular internet auction site.

Researchers, who had no prior knowledge of where the disks had been bought and what they contained, were able to identify the organisation or individual who had used more than 50 per cent of the machines. In 53 per cent of them, they found a username, and 57 per cent had information from which the organisations could be identified.

These ranged from a large leisure services industry organisation and a financial services organisation to a surveyor, a primary school and universities. Name, addresses and contact details of employees were found on some computers and home office machines contained detailed information about children.

Twenty per cent of the disks contained financial information such as sales receipts and profit and loss reports. And 8 per cent had information about the computer network of the organisations, including server names.

A failed or partly successful attempt had been made to delete files from 48 per cent of the machines but only 17 per cent of all the disks examined were totally blank.

Dr Andy Blyth, principal lecturer and head of the Information Security Research Group at the university, said: "In particular, the project wanted to examine the extent to which commercial data was available via computer hard disks on sites such as eBay. We are used to this kind of work because we have functioned as expert witnesses for regional and national hi-tech crime units. But the results were still surprising.

"Companies have an obligation to dispose of data when it is no longer required and many of the organisations involved are now launching investigations into how this information has ended up in the public domain."