Dragging desktop Icon error/esktop freeze Saucy Ubuntu 13.10

[e]

several times of late I drag an icon and release it and then
the desktop freezes up after an error popup window pops up
and I can''t close the window or open any programs from the program bar
and have to reboot to free the desktop

the latter seems like a new developement hence this note I have an 
updated system as of 2 APr 2014

perhaps unrelated at boot up on the text screen leading to desktop 
something about caching mode sd6 sd7 (perhaps just a usb device/drive 
report)