Fellow PC users,
I recently inherited a five year-old Dell 2400 Dimension.  My daughter, more computer-knowable than me, has been here about a month helping me downsize after the death of my wife of 61 years.  I seem to be gliding down an ever steepening path and seem to be losing, among other things, whatever computer smarts I once had.  I did install a wireless network for my several computers in the new home and have just added this Dell to the network.  My daughter took the machine to a local shop and they replaced the old operating system with Windows XP, Home Edition with SP-3.  Every time I boot the machine I see a warning message in the System Tray indicating that I may be at risk as Anti-Virus software might not be installed and to click below to correct this.  Wen I do that I see an option to obtain/install one of four software packages.  However, along with this there is another warning to not install one if there is already one on the machine as they might not get along with each other.
So that begs the question of how does one go about finding out if the machine really has no such software installed?  Is there a simple test that I can make or do I have to head back to the professional in the local shop?  I've looked (I think) at what's on the machine, and don't recognize any with which I'm familiar.  TIA.
Lewis Emerson 

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