Hi, my Sony VAIO laptop with Windows Vista (VGN-NR260E) won't allow me to login to Windows, and instead is stuck in a loop or cycle. There are many different screens that appear, depending on what I select or push on my keyboard according to different types of prompts. After manually shutting the laptop down and starting it back up using the power button, the computer will go from the Windows Vista loading screen (with the loading bar blinking below for a couple of seconds), to the Windows Diagnostic tools page. This page offers up the choices to start the computer up normally, or in last configuration, or safe mode with networking, or safe mode. None of those selections allow the computer to bring up Windows and the login screen for windows. There is no plain blue or black screen (every screen either has written text and instructions or at least a blinking bar). And doing the Windows Memory diagnostic (the blue screen with white text) also does not make any difference, regardless of the size of the cache or length of the 'test mix'. I wanted to check and see if there is anything else I can try on my laptop to operate it like normally, or if it's time to have the operating system reloaded on it. Basically, this seems to probably be a virus, and I'm honestly checking to see if there is any kind of keyboard 'trick' or shortcut that I can try. There are a few more bits of information that I can give about this situation and activity with my laptop if anyone thinks that it's salvagable. If not, thanks for reading, at least!