Anti-virus company Symantec has warned of a new variant of the Melissa virus which could strike UK companies later today.
The US-based company said the W97M.Melissa.U virus, a strain of the Melissa virus which caused havoc in April this year, has already hit several large US organisations.
Symantec's anti-virus research centre said it has not had any reports of infections from the UK and Europe, but warned that it could start to affect businesses this afternoon.
Kevin Street, technical manager from Symantec Europe Middle East and Africa, commented: "This virus has not hit the UK yet. However, we could see infections within the UK as US companies with global offices come online later today," he said.
He added: "We don't know how pervasive this virus will be. As members of the Web community, companies should take responsibility for not proliferating it."
Street said if you get an email with the following subject header - subject: pictures USERNAME, body: what's up? - "Don't launch the attachment, and contact your systems administrator straight away."
He explained that the USERNAME would be the name registered in the local copy of Word.
The virus will attempt to use Microsoft Outlook to email a copy of the infected document to up to four email addresses (this may include an email address that contains an entire address book). The virus will insert the following text into the active document: "Please check Outlook Inbox Mail". It will then delete several files when the infected file is opened, making the system unbootable.
Symantec said updates offering protection from the new variant of Melissa are available for download from its website.
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