My bad, i should give you a explanation, a LEAK means the map is not enclosed properly(or have some entity outside in the void), for games like cod and counter strike, the map needs to be full enclosed by skybox in Radiant, not open to the void, its not something you need to reinstall everything to ...

[code]ERROR: in map: C:\Program Files (x86)\Steam\steamapps\common\Call of Duty World at War\map_source\nazi_zombies_snowday.map
ERROR: Entity 27 misc_prefab at (296 72 16) has no model
ERROR: Prefab '_prefabs/default_missing_prefab.map' not found
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