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how are you your password eager to see you meeting notice look, my beautiful girlfriend darling

In an attempt to trick users, the virus can also appear as a message warning about the danger of the Klez worm and urging users to execute the attached file.

It also includes a note telling users to ignore any warnings from anti-virus software companies that the attachment is infected.

The new version of the worm contains a second virus called Elkern which attempts to infect all executable files on an infected machine.

Anti-virus experts say home users are more at risk from this worm as they do not update their virus protection as often as businesses.

The new version, the Win32.Klez.H@mm worm, is a variant of the mass-mailing Klez worm that first surfaced in October last year.

The Klez worm reappears periodically, most recently in March, when it caused minimal damage.