I’ve run into similar issues and it stems mainly from having duplicate assets in your scene.
To check this, you can open a simple level and place in two different assets. If it builds fine there, yet fails on your map it’s most likely having copies of assets. This happens because Unreal writes a cached version of the scene, and if it tries to build a cache for T_Dirt01 and a different uasset with the name T_Dirt01 it tries to write it to the same location, and that’s why it bugs out with the file access error.
If you comb through your map, and look for copies of Materials, Static Meshes and Textures. Try to delete and reference duplicates, or rename them if they simply share a common name like box_01. I’d recommend going into Window>Statistics in your level and it will list the names of various assets which might be causing the issue.
Hope that was helpful, good luck!