"No Writable WD SmartWare Partition Found"

Is there a way to reinstall the thing or is it a gonner???

Do you mean WD SmartWare software or get drive back to use it as backup?

You can simple re-format using Disk Manager/Windows or Disk Utility/Mac to be used by computer and/or with WD SmartWare software.  Once drive format is recognized by the WD SmartWare you can use it for back up or storage.

I am assuming the drive is spinning (not physically broken state).