How to unistall safe finder?

I don't know how is possible but this program is impossible to delete, so when I wont to search for something, the browser first uses Google as the default then it redirects me to yahoo with this safe finder. Ad if I want to search the page of Google (google.it in my case) the browser blocks the connection and says: "Connection broken: potential security risk". I don't know what to do. The strange thing is that the problem is just on the main browser, if I change with chrome the same is there!