From "a Witch Who Casts Viruses Out of Computers With Magic":
I got contacted by a small business owner in Marin county. She had a couple of different viruses and she called me in. First, I cast a circle and called in earth, air, fire and water, and then I called in Mercury, the messenger and communicator. Then I went into a trance state, and all I was doing was feeling. I literally feel [the virus] in my body. I can feel the smoothness where the energy’s running, and then I feel a snag. That’s where the virus got in.
Then I performed a banishing ceremony. I used a black bowl with a magnet and water to draw [the virus] out. Then I saged the whole computer to chase the negativity back into the bowl, and then I flushed that down the toilet. After this I did a purification ceremony. Then I made a protection spell out of chloride, amethyst, and jet. I left these on the computer at the base where she works.