USB port or flash drive not detected

• Try the flash drive in another port and on another computer. This shows whether the drive or the port is faulty.
• Restart the laptop with the drive removed, then plug it in.
• Open Disk Management (right-click Start). If the drive shows without a letter, assign one.
• Update the USB controller drivers in Device Manager.
• Turn off USB selective suspend in Power Options.

Bent pins or a loose port need a technician. Do not force the drive in.