I have a Toshiba Satalite with vista home premium and I am having problems with my screen flashing when I first login. The screen turns black and then turns blue for like two or three seconds. Also over the pass few days I have lost about 4 or 5 GB of free space on my hard drive and have no idea where it went. Also malewarebytes and trend micro didn't fix the problem. Please tell me what I can do to fix this problem.