Lost images

We loaded images into capture one from a CF card by highlighting all images and dragging and dropping in created folder. Images appeared in previews. We loaded another card into the same folder and images appeared however, we received a "insufficient disk space issue". Images were reviewed and card was ejected. Later went back to look in folder where images were and we have lost all images from that session. We looked in trash and appears that nothing went to trash from that session either. Could we have lost the images even though the previews were created and able to be viewed. Also, searched entire hard disk for images via windows and can't find anything???? Please help??