If that mysterious symbol is the usual icon, than it's dependent on the file type. So if the symbol if different from the symbol of a .cdr file, it's not a .cdr file. What's the file extension (to see that, set Windows Explorer to show file extensions in stead of hiding them).
Most likely, for this file you have to return to latest backup.
I have a problem in attempt to open the CDR file that I think, failed. It is the 2nd time when it happened to various files.
The file still is found in my external disk drive, but has a symbol near it which it had no before (a green pencil as a symbol in my program files for CorelDraw X3). When I press it, it opens in Corel, but as a blank page. I released this file, or I can some how return it?