Terrain LOD meshes were generated while a plugin or mod which was made for another game was installed.
For example, do not install mods with pre-made LODs made for Skyrim to Enderal.
Installing LOD mods that were made by using xLODGen/DynDOLOD is pointless when generating LOD with xLODGen/DynDOLOD.
Installing LOD mods made for Skyrim and Tamriel into Enderal is doing something uniformed. Make sure to always read descriptions and documentations of mods and tools. Use the official DynDOLOD support forum in case of questions for qualified advice and answers.