I had one client that keep complaining that his computer is very slow, plus it cannot access any Microsoft or anti-virus website. A quick search on the internet suggested that his computer has already been infected by a virus called Conficker, once a very serious virus in computer network, and of course still infecting numerous of computer around the world.  My previous experience with Conficker virus seems to be a little bit different, with registry editor and folder option in Windows disabled by the virus. But it doesn’t seems to be the case for my client computer. Of course, ideally, formatting the computer will be the best solution, since the computer has been badly infected (I am pretty sure it is not only the conficker viruses inside), as the anti-virus software installed was disabled by the virus as well. But he insist that the computer is best not to get formatted, as it has some very important networking and printer sharing. So to make him happy, I try to solve the viruses instead of doing a clean install of Windows.