UNless you have a copy of the IDB from before you re-installed, export to MCF file is not going to work. You would have to switch to the old IDB version, expor tthe MCF file, but the current IDB back into place, and import the MCF file
Also a Scan is not going to do anything but read the header file to see if it is valid DP media, and if it currently in the IDB (if not, it is supposed to show 'Data Protector Foreign'). You would need to Import the media to get the data back into the IDB