Cant write successfully to USB devices

[Robert Moskowitz]

This is on a Lenovo X120e with current f17 patches.

Both to my SD slot and to USB drives very recently, writes to USB drives 
is not working.

It seems to work.  I can see the files and open them.  Then I unmount 
the device move it over to another system and that system cannot read 
the files.  For the SD card, I have tried removing the partition, 
recreating it, and copying the files.  It still fails.

Interesting, I successfully copied the files only my Galaxy III (New 
Verizon software makes the III mount as a Win install device, but going 
to 'Tethering' gets it mounted properly showing all directories) and 
then mounted both the Galaxy and the SD card on the other system and 
successfully copied files to the SD card and opened them.

The other system is back-leveled on F17.  Don't know if this is a 
software or hardware problem.  But it is recent.  Only early in the 
week, I could copy files.

How can I troubleshoot this?