People who are buying or selling second-hand laptops, tablets and smartphones are being urged to follow new consumer guidance in order to protect their personal information and prevent it from falling into the hands of cyber criminals.

January sales often sees people looking for new personal computing devices while those who've received an upgrade over Christmas could be looking to sell their own model. Buying and selling second-hand devices can provide benefits to users, but the UK's National Cyber Security Centre (NCSC) has warned that if these devices are not properly secured, valuable personal information could be exploited.

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Users who sell their devices without wiping them first could be handing their personal information and passwords on to others who might be unscrupulous when dealing with that data.

The guidance provides instructions on what users should do to reset their Android, Apple, Google or Windows devices to factory settings in order to erase all content and personal data, including messages, contacts, photographs, browsing history, Wi-Fi codes, passwords, and any apps installed.

But it isn't just leaving data on old devices that could put users at risk from cyber criminals