Why wasn't I protected from the RSA {cryptosystem}? I have it now.

The RSA {cryptosystem} popped up on my laptop and I am very upset Webroot did not stop that from happening.
 
Webroot practically runs constantly to get rid of the same 4 or 5 viruses it seems to repeatedly stop and get rid of.. Yet it failed to stop a real attak on my laptop. Now I am burdened with this virus and don't know how to stop it.
 
I am not happy with Webroot right now. Please remove it from my laptop?
 
Thank you.