Thanks to the info found in this forum I was apparently able to remove the so-called Trojan-Bookmarker.D in the sense that it does not set the browser homepage or create the bookmarks anymore. Still I am very concerned about the presence of this virus in my system. In particular, I noticed that explorer (not the internet browser) always weirdly refreshes the first time I access it after I boot (never done it before) and it lets me think that is being replaced by a virus controlled version. After all, once the bad guys have been able to enter my system.. why should they leave it?

You may still have entries in your Registry. Or BHO line looking for the .exe file that reloads find4u when you open your browser. Do a search on find4u removal and go through the steps again to make sure you eliminated all the files related to this trojan. Also do a search for winlogon.exe and make sure the version you have is from Microsoft. Do this by right clicking on the file and check properties-version the company should be Microsoft not $.