I had about 6 GB on a 8 GB Lexar USB flash drive. I inserted it and verified the info on it. I right clicked the icon and hit "Copy Lexar". It took a few minutes and when I came back to the iMac the icon was gone and I could not find the file anywhere on the computer. I took out the flash drive and re-inserted it, but it would not bring up the icon. How do I find this file and how do I get the Lexar flash drive working again. This is a very important file I need.