Internet security firms warned computers users to be vigilant about protecting their IT systems yesterday in the wake of the second major computer virus to hit Ireland in just over a week.
Several Irish companies and public bodies are thought to have been infected by the latest computer virus, which has been appropriately named SoBig.
The SoBig virus spreads when unsuspecting computer users open file attachments in e-mails that contain familiar headings as "Thank you", "Re: Details" or "Re: approved". Once the file is opened, SoBig, which first appeared on Monday, scours the computer for e-mail addresses, checking in Word documents, Internet logs and e-mail inboxes.
Designed like mass-mailing spam programmes, it then sends scores of messages to the addresses it has collected.
Mr Stephen Breen, director of security services at the Irish security firm Priority Data, said the SoBig virus was slowing down e-mail systems in many firms. He confirmed that several regional technical colleges' e-mails systems had been infected.
It is believed that Trinity College, Dublin was forced to shut down some of its computer systems yesterday, although no comment was made by the university.