transfer photos from computer to Cruzer flash drive?

DONT DO IT before calling sandisk help…I followed the directions from sandisk website…I dragged and dropped my pics…message said OK…then when i checked, my pics were all LOST…spent an HOUR on the phone with SANDISK technocian trying to HELP me recover, but my pics are lost.  He said I should have chosen copy and paste instead of drag and drop, (which is what sandisk recommends in their instructions)…then to further upset my day, he offered me a SANDISK program i could PURCHASE to possibly recover my lost pics…for $39.95…hmmmmmm