U disk Startup disk failed to make the cause

Possible reasons first, the motherboard does not support U disk startup (or support of the imperfect);

May cause two, some DOS software (especially to disk operation Class) to the USB disk support may not be very good;

Possible reasons three, U disk is the new hardware after the DOS, the kind of more complex, and the vast majority of USB devices are no DOS under the driver, the current use of the basic are compatible drivers, so there are some problems are inevitable;

Possible reasons four, the U disk itself quality problems;

Possible reasons five, often on the U disk has incorrect operation, such as XP, 2003 directly plug a U disk, rather than through the "safe removal of hardware" to uninstall