USB devices can become nonresponsive for several reasons, including unsafely interrupting a data transfer or if a guest operating system driver sends an unsupported command to the device.

The USB device is nonresponsive.

A data transfer was interrupted or nonsupported devices are being used. For example, if a guest driver sends a SCSI REPORT LUNS command to some unsupported USB flash drives, the device stops responding to all commands.

1

Physically detach the USB device from the ESX/ESXi host and reattach it.

2

Fully shut down the host (not reset) and leave it powered off for at least 30 seconds to ensure that the host USB bus power is fully powered down.