Real networks used to try to trick people into buying their software when they gave away a perfectly good free version. The moment I noticed that they were doing it I stopped trusting them.
Avg - the virus people - seem to be doing the same. I use their free version. Just lately I've been getting a wee pop up telling me I need to upgrade to version 8.0 and when I follow that link ... it seems to be trying to sell me an upgrade. Perhaps I'm just being daft ... but now I don't trust them.
Here's the free version - which I found via google.