What Causes Windows 7 Blue Screens?
If you are getting a Windows 7 blue screen on startup, it means something has been incorrectly installed on your system. The culprit will most likely be an incorrect driver that is causing the system to crash, or it could be some recently installed software that is conflicting with another programs. Since drivers are technically software, it could be a combination of both.
The first thing you should do to help resolve this problem is to remove or disconnect any new hardware you have recently installed. If it is some USB device, remove it from the USB port and see if you still get the blue screen. If not, try plugging the USB device back into the port and see if Windows 7 gives you a blue screen. If it does, you have located the source of the problem. Try the same thing with internal components like sound cards, network cards, and so on. With USB devices, you may also want to try plugging them into different USB ports.
In addition to incorrect drivers being installed, it could be that you are trying to connect a bad piece of hardware. Are you sure the device you are trying to connect is actually functional? Try testing the hardware in another machine, if you have one available.
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