Lost Bootloader MI 4C [HARDBRICK] and no Qualcomm Device in Device-Manager

[tonfilm]

Hello, for some reason i cannot get my phone into fastboot. The main problem is that my PC with Win10 x64 does not find any device when i plug the USB cable in.

I have read in many forums that i have to discharge the battery so that the red LED blinks and then plug the USB. This is the case, but no device is found by windows...

any tips on how to get the qualcomm thing work so i can use MiFlash to flash an official ROM?

 

[edisonpaul4]

Almost impossible to loose fastboot, what did you do? Have you done this before? Are you sure windows cant find your device? I had a problem that for a few hours after brick my phone, windows didnt recognize my device as Qualcomm device... windows recognized my device as "something I cant remember", and suddenly after I connected my device to wall charger for a few minutes, suddenly apear in my computer as qualcomm device.

 

[Rackor]

probably a dead battery or broquen usb port. try another cable