I have an Asus K50IJ laptop which was purchased at the end of 2009. Three weeks ago, I went on a trip and took the laptop with me. The place where I stayed at turned out to have no WiFi, so the laptop spent three weeks lying basically unused on the shelf (I did turn it on once to check if I could find any wireless network, and it worked perfectly fine at that time). Today, I came back home and attempted to turn the laptop on. The first thing that welcomed me was the "This copy of Windows 7 may not be original" (while I run a fully legal copy of Win 7 Home Premium, upgraded from Vista). A window came up offering me to "purchase a legal copy of Windows 7", but having done that half a year ago, I clicked Cancel. The loading seemed to take a little bit longer than it usually does, but in the end, Windows loaded. I tried to open my browser, but it froze the system, so I turned it off by holding the power button for 6 seconds. When I turned the laptop on again, it showed nothing but a black screen saying "A disk read error occured. Press Ctrl+Alt+Del to restart". I tried doing that, but it just shows up the same message. Same when I tried turning it off with the power button and turning it back on. What should I do?