It's a rip-off - don't go near it.
Keep your PC healthy with a decent (free) anti-virus and do a weekly scan using Malwarebytes Free (used by many in this forum). Also try SpyWareBlaster (also free).
If you want to clean up your PC, try Ccleaner from Piriform click here (it is entirely free to download and use). Again used by many in this forum.