Spybot - Search & Destroy
Full user review
"This program has saved me more then once."
If this program finds something too dangerous to remove it will ask your permission to do a boot scan of your computer. This has happened 3 times for me in 6 or 7 years. On one of those hits, I researched and discovered I had actually become somebody's bot, and I was under their remote control. Spybot removed it, and I actually sent Spybot a donation on that one! Spybot has a feature to immunize your computer against such attacks, that I update regularly. I have double checked Spybot against other programs of this genre. It has seldom given me a false hit, and never missed anything.
It does not come with automatic upgrades.
Spybot is an essential program for me.