You can go to rca.com and go through their support pages to get to the rca lyra 2840 page and download the firmware upgrade, I believe that is the one I used. Here is a direct link to the firmware upgrade: http://www.rcaaudiovideo.com/Cultures/en-US/FirmwareUpgrade161
It will install the files you need.
Your computer must have deleted the files. There are two folders that are on your lyra when you first get it, they are: lyrahdd_playlists and lyra_sys. The later is the one that is important it has all the information for the device to run.
If that doesn't work just e-mail me and I can send you the two folders from mine, it should work. nosmada@gmail.com