External USB HDD not usable after con...

Description:
Windows detected a new device attached to your computer, but could not find the driver software it needs to make the device usable. Each device manufacturer typically includes driver software of a CD that comes with the device, or as a download from its website. The hardware ID of your device is USBSTOR\DiskSAMSUNG_HM121HC_________LS10.
Problem signature:
Problem Event Name: PnPDriverNotFound
Architecture: x86
Hardware Id: USBSTOR\DiskSAMSUNG_HM121HC_________LS10
OS Version: 6.0.6000.2.0.0.256.6
Locale ID: 2057
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