USB Thumb Drives
When you click the "My Computer" icon in KDE and attempt to access your thumb drive, you might receive an error message about "flush".
Right click the link for your thumb drive, select "Properties", click the "Mounting" tab and uncheck "Flushed IO".
Now you should be able to access the thumb drive. You might even be able to check this option again later.
If you turn on Desktop Device Icons (kcontrol) you may also get the "flush" error. Right click the icon and turn off the "Flushed IO" option.