USB problems split between the device, the cable, and the port. Eliminate each in order.

1. Try a different USB port

Specifically a different type if possible. USB 3.0 ports (blue inside) sometimes have power issues with high-draw devices. USB 2.0 ports (black) are slower but often more reliable for keyboards, mice, USB sticks.

Move to a port on the other side of the laptop — USB controllers are sometimes per-side and one can fail.

2. Try a different cable

USB cables fail with depressing regularity. The "charging only" vs "data" cable confusion strikes everyone at least once. Swap with a known-good cable from another device.

USB-C is especially bad here. A cable that charges your phone may not carry data, video, or full power. The cables that work for everything are labeled "Thunderbolt 4" or "USB4".

3. Try the device on another machine

Plug it into a colleague's laptop. If it works there, your laptop is the problem. If it fails there too, the device is the problem.

4. Check Device Manager

Windows + X → Device Manager → look for warning triangles. Common entries:

  • Unknown device under USB controllers — driver missing
  • USB Composite Device with errors — try uninstalling, then unplug and replug

Right-click and uninstall any errored entry, then unplug + replug the device. Windows reinstalls.

5. Power management on USB ports

Windows aggressively turns off USB power to save battery. This causes USB sticks and external drives to disconnect mid-use:

  1. Device Manager → USB Root Hub (you may have several)
  2. Right-click → Properties → Power Management tab
  3. Uncheck Allow the computer to turn off this device to save power
  4. Repeat for each Root Hub

Reboot.

External hard drives specifically

A 2.5" external drive often needs more power than a single USB port can deliver:

  • Use the dedicated cable that came with the drive (it's often a Y-cable with two USB plugs — both plug in)
  • Avoid USB hubs — plug directly into the laptop
  • Listen for the drive spinning; if it's silent, it's not getting power

USB hubs

Cheap USB hubs cause more tickets than they solve. If devices fail on a hub but work direct, the hub is the issue. Powered hubs (with their own wall adapter) work better than passive ones.

Phones connecting as "charging only"

If your phone shows up as "charging" but you can't see files:

  • On Android: pull down the notifications shade → tap the USB notification → choose File transfer
  • On iPhone: it asks to "Trust this computer" on the phone screen — tap Trust

When to ticket

Open a ticket if:

  • A single port consistently fails for all devices (port is dead)
  • A device works on a colleague's laptop but not yours after driver reinstall
  • You see USB Power Surge errors — that's a hardware fault