If you can't find the place in Photoshop where it aquires devices, and without Photoshop I can't help much, you can reinstall the scanner.

Here's the fast and quick answer.

Unplug the scanner, go to My Computer, Control Panel, System, Device Manager and remove the scanner from the device list.

Shut down the computer.

Connect the scanner and start the computer. Windows will find it as a plug and play device and re-install it.