you can download and run "Stinger" for a second opinion. It's a small stand-alone scanner from Mcafee for certain viruses including netsky and it's variants. It's free.
http://vil.nai.com/vil/stinger/
The ISP might be detecting something from a spoofed address.
My Dad has run his antivirus program and says no virus found, however every now and then with antivirus provided by his internet company - it says he has the netsky worm.
How does he remove this worm from his computer??

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