Hi, look forward to receiving attention to the problem I am having. I have been using a Dell i5, Window 10 computer, I have been using it for 3 months now but it is very stiff and slow, I think it is caused by a virus. I want to have the best free anti-virus software available today, I have also searched but the whole non-reputable software causes more virus infection, looking forward to the honest answer, thank you.