Not recognising any external USB devices. Why???

[binks]

Suddenly, from one day to the next, my W10 stopped to recognise any externally connected devices. I've tried using my USB hub, I've tried plugging 4 different usb->micro USB cables(to get the faulty cable out of the equation) to the front of my PC as to the back where the majority of USBplugs are. But nothing. My devices only detect that some sort of power has been connected. I can't transfer any data between devices. It's not only one specific device. It happens to whatever I plug into USB. Regardless if it is a flash drive, my camera, tablet or my phone. It did work perfectly but one morning when I got up from the bed and wanted to transfer some files from the PC to my phone as I needed them for work, I just couldn't do it.  The strange thing is that device manager doesn't show any errors in the USB section of the tree. So what's going on here? What happened??