The "USB device not recognized" popup means Windows saw something appear on the port but could not identify or start it. The cause ranges from a worn cable to a failed driver - and because the message never says which, the fastest way through is a fixed order of checks, from the ten-second ones to the deeper ones.
Quick answer
Unplug the device, plug it into a different USB port (on a desktop - a rear port), avoiding hubs and extension cables. If that changes nothing, shut down completely, unplug the computer's power for 30 seconds, boot and try again. These two moves resolve the majority of cases; the driver-level fixes below cover the rest.
Worn cables, charge-only cables, overloaded hubs and damaged front-panel ports are the most common cause - the data lines never make a clean connection.
Windows found the device but its driver errored out - the device shows as Unknown Device or with error codes like 43.
After sleep/wake cycles or a power glitch, the USB controllers themselves can wedge - a full power cycle or reinstalling the root hubs resets them.
On a fresh Windows install, USB controllers may run on generic drivers - ports work partially or misbehave until the chipset package is installed.
control powercfg.cpl,,1 (or open Power Options, Change plan settings, Change advanced power settings).Keyboard and mouse may drop for a moment during the restart - that is expected while the hubs reinstall.
If you do not know the exact model, several devices need attention at once, or the manual route did not find a match - Outbyte Driver Updater identifies your installed hardware automatically and updates the drivers from official sources, with a backup before every change. The scan and diagnosis are free.
Download Driver Updater Downloads Outbyte Driver Updater for Windows 11, 10, 8 and 7. Free 2-day trial, no credit card required.Usually yes - "not recognized" is a connection-level failure, the data on the drive is untouched. Fix the connection or read the drive on another computer. Avoid formatting prompts until the drive is properly detected.
That narrows it to your computer: a stuck controller, a failed driver or a weak port. Run methods 2, 3 and 5, and make sure the chipset drivers for your board are installed.
USB 3.0 controllers have their own drivers. If blue (3.0) ports fail while black (2.0) ports work, reinstall the USB 3.0 controller in Device Manager and install the chipset package for your motherboard.