We would like to remind computer users that spam emails regularly circulate asking users to click on a link. A recent example was a link to a greetings card that arrived during the summer holiday period. Clicking on the link installed a Trojan horse program that gave the attacker control of the user's computer. Several Windows PCs at CERN were affected and needed to be re-installed from scratch.

Users need to be vigilant about such tricks and remain cautious about clicking on links or opening attachments in any emails they are not expecting. Antivirus systems may not be able to detect all of the latest viruses, which are now highly sophisticated.