For some reason the wireless adapter isn’t detected by Windows. Either the device has failed, has been disabled or the driver is missing. If it’s a missing driver, the wireless adapter may be listed in the Device Manager as an unknown device.

Right click the start menu button and select Disk Management from the menu. Select New Volume D: and delete it. Then select Local Disk C: and open the Action menu at the top of the window to extend the volume into the unallocated space.