recent issue in bridge

Got a question...  This issue happens in my CS6 and my CC Photoshop / Bridge. On certain times when I download raw files and then  go to bridge, instead of seeing a small version of the photos for that entire date, all the raw photos will only show the raw icon (not sure what to call it). When I click on any of them, it says camera raw cannot open this file. But for most of the other shooting dates, my raw photos can be seen and they open up just fine in ACR. Please see my scan below to understand what I'm seeing when this issue shows up.  This problem just started about a week ago. What is happening to cause this issue and how do I fix it ?  Thanks.