Hello I've ordered at Amazon a copy of ESET NOD32 Antivirus with a rescue CD. Because of Christmas business the shipment would take longer. Next week the actual Antivirus software (McAfee), which runs in my computer, needs renewal. I will change to ESET. That means I'll deinstall & "clear" McAfee. I think, I can bridge the time with an ESET NOD32 Antivirus to test 1 month free. I'll get it online. When the CD package comes after Christmas, can I install it "above" the "test software" without deinstalling & clearing before? Thank you.