No Longer Able to access any FMB Missions
 

I can no longer access any of the FMB missions, the ones that came with game, ones I have developed and ones others have developed.
I cannot get past the Player Plane Screen that always defaults to the Spit IIA regasrdless of the a/c that has been selected in the FMB itself.
I have deleted all the cache files in the CoD cache folder and tried to verify cache files in Steam, but it just sits there at 0% and nothing happens.
Has this happened to anyone else and if so, what was the fix?