I don't think that this is a Worm in your computer, I think it is just Norton syaing there is a Worm trying to nfect your computer that is not getting in. Try closing all running apllications and doing Adware, Spyware, and Virus scans, and cleaning out your computer of programs you don't need or don't know what they are. I know cleaning your computer of programs and objects sounds a bit weird for this sort of thing but it can sometimes help.
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