Bad data line.
No hard power allocated to the computer chassis and then re-connecting the hard drive at the data line, a hard disk or exchange data cable reconnection.
U disk boot disk for their own reasons.
Undetectable hard drive case, then we can re-create the boot disk U disk after its own problems of course U disk boot disk can also lead into the PE, we recommend the use of U help U disk boot disk creation tools, the good compatibility.
Hard disk AHCI mode leads to find the hard drive.
U disk loading system can not find the hard disk solution is to change the mode to IDE hard disk can be
Lenovo notebook, for example: the just-machine press F2 to enter the BIOS, (Note: If you do not know specifically what, please look at the screen to enter the BIOS, then just getting closer, there will be prompt) to enter the BIOS, it can be up and down
Key adjustment options, and then select Advanced, then select the SATA that option, press the Enter out two options, and then select AHCI
That option, he can switch to IDE.