This could be because you are not removing the device safely. Check the icons on the bottom right of the taskbar. You are looking for the icon that looks like the one highlighted in red. If this symbol is not showing, click on the left-pointing arrow on the left (shown here as right-pointing because all the symbols are showing) to expand this group to show all symbols.
Left click on this and from the pop-up select the device by left clicking on it. Wait until the following message is displayed.
Click 'OK' and then remove the device.
4 x 4GB DDR3-1600 Corsair Vengeance CMZ8GX3M2A1600C9B (16GB)
Graphics card(s)
MSI GeForce GTX770 Gaming OC 2GB
Sound Card
Realtek High Definition on board solution (ALC 898)
Monitor(s) Displays
ViewSonic VA1912w Widescreen
Screen Resolution
1440x900
Hard Drives
OCZ Agility 3 120GB SATA III x2 (RAID 0)
Samsung HD501LJ 500GB SATA II x2
Hitachi HDS721010CLA332 1TB SATA II
Iomega 1.5TB Ext USB 2.0
WD 2.0TB Ext USB 3.0