SecureAccess for MAC

Hi Ed,  I’m a senior lady and I’m not an expert on computers.  Can you help me please?  Maybe some things I did sound stupid to you, but I’m doing my best here, I’m alone and no one else to ask.  I erased my USB because I had double songs in my iTunes.  I removed all the double songs in iTunes so the next step would be to erase the songs on the USB and download again.  However now that I have plugged the USB into my computer, it shows up as Remote Disk but it doesn’t show on the desktop.  The way I downloaded my songs onto the USB before was that I went to iTunes and in there I saw an icon for the SanDisk and I dragged the file with my songs onto the icon and it downloaded.  As I said, now I cannot see the icon for the SanDisk even though it is plugged into my computer.  If you are familiar with MAC computers and iTunes, can you please help me find the SanDisk so I can download my songs.  Thanks.  Kathy