USB 3 0 problems in windows 8 1 - Usb Hard Drive disconnecting, etc...
If you experience having problems with devices that use 3.0 techonology, like for example external hard drive, this should work for you. Or not, but it is worth to try I think.
Use these notes for registry and regedit
Use regedit with admin rights
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\usbstor
Right-click usbstor, New, Key
As name type YOUR two 4 character codes
example: 10580748
On the right side right-click, New, DWORD 32-bit Value (even if you have 64 bit windows)
As name type DeviceHackFlags
Enter as value 400
Restart computer
UPDATE
FInally I have found what was wrong, it was freaking usb 3.0 WD cable!!!!!! Buy a cheap cable 3.0 on ebay and it might work. I wasted so much time and not look where the real problem was. In freaking cable!!!