When I plug in usb flash drive, or even my camera and open File Manager only old data that was previously on usb drive (or Camera's memory card) is shown. I can't open any of those files or see any new listed. Is there any way to clear usb cache, some temp files or something where that data is stored. I am using Lubuntu 12.04.
Solved the problem by installing Nautilus. Now I use it as default file manager and have no problems stated above or any other at all.
I'd recommend the PCManFM re installation:
Remove existing PCManFM.
sudo apt-get remove pcmanfm
Install PCManFM again.
sudo apt-get install pcmanfm
After that reboot the system to see the changes.