5 reasons why USB devices are not recognized under Windows 7 flagship system

1, in the USB read and write must not be pulled out, or may burn equipment, win7 system taskbar more than the amount of USB device icon, open the icon will be shown in the list of U disk devices, select the device to deactivate, and then you unplug the device, this will be more secure.

2, may be the USB interface voltage is not enough. When the mobile hard disk is connected to the front USB port, it is possible that the system can not recognize the device de fault, because the mobile hard disk power requirements of relatively strict voltage, the front interface may not provide enough voltage, of course, inferior power supply may also cause this problem. Workaround: Do not connect the hard drive to the front USB interface, replace the inferior low-power power supply or try to use external power of the hard disk box.

3, motherboard and system compatibility issues, the most famous is the NF2 motherboard and Usbde compatibility issues. If you encounter this problem on the NF2DE motherboard, you can first install the latest DENFORCE2 dedicated USB2.0 drive and patches, the latest motherboard patches and operating system patches, or not to try to refresh the motherboard Debios generally can be resolved.

4, System or BIOS problem, when you disable USB in the BIOS or operating system, USB devices will not be recognized in the system. The solution is to turn on the USB device associated with the de option. On the system boot press F2 or DEL key, into the BIOS, the Enable USB device select Enable.

5, the front of the USB cable connection is incorrect. This type of failure occurs when the motherboard is connected to the DEUSB line and the Chassis de front USB interface, which is likely to cause the USB device to burn down due to a positive or negative connection. So as far as possible using the chassis back to the Deusb interface, but also less use extension cord. It may be a problem with the fracture, change the USB port to see.

Also note: Everyone in Windows format when you want to choose FAT, do not select FAT32.