Sansa c140 - can't open folder to drag/drop music


I have had my sansa for about 6 months, so far no problems. I am going on a trip and decided to put new music on my player and that’s when my problem started. I plugged it in my computer, found it was in MSC mode, and unplug it. And found that all my songs that were on there were gone, just said empty. I didn’t really care since I was putting on new songs anyway, just kind of weird, anyway selected autodetect on player, re-plugged it into my computer and now it was in MTP mode. And my computer brought up options of opening it with WMP or doing nothing. I don’t like WMP, I just want to drag and drop songs, much easier that way, but I can’t find the sansa player anywhere on my computer. I have looked all over, and searched for it. How do I get the Sansa media folder to come up and where did all the songs I have on there go? Please help!