I have IL46 v4.08m and I've suddenly found that my desert and Italy_DF maps do not load. When I try to run a mission withnthose maps I get a load error. If I try to view the mission with Mission Builder they never appear. I don't know where the maps are stored or generated.
Is there any way of recovering them.

Could it be you are using an ATI card?

If so, in ATI's control panel, switch off the 'Catalyst AI' (or maybe change it to standard...)

Many thanks for your reply. What I should have mentioned is other missions that do not use the desert or Italy_DF maps are okay. I believe these maps were part of v4.08m. I could try reloading the update but I'd rather fix the damaged file(s). Is there a way of locating the map files.

Problem solved I found the corrupt maps files and replaced them - case closed